I just want you to check my grammar since I'm planning to send this text to a law enforcement and maybe make this text sound more formal.

to a law enforcement body; law enforcement itself is a concept, and a process and cannot be used as a noun in singular.

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Since November we stopped sharing nude pictures because of one accident.

We stopped exchanging nude pictures in November following an accident, and haven't continued since.

Once, my father almost came across that I used to take nude pictures, but somehow I came up with a lie and he believed me.

Once, my father almost discovered (came across is better for actually physically finding a photo, rather than learning about a tendency) that I had been taking nude photos, but I managed to lie and convince him this wasn't the case.

It got (the name) very scared and he stopped asking me for nude pictures.

This frightened (name) very much and he stopped asking me for nude photos.

Sometimes I tried to make up lewd conversations, but he mostly didn't want to have them.

Sometimes I would try to engage in lewd conversations, but largely he wasn't interested in them.

Since that period, he started ghosting me, which led to decreasing my feelings for him.

Since then, he began to ghost me, and my feelings for him have since weakened.

On the 30th of January of 2023, after ghosting me for about a week, he told me that he wants to stop talking with me because he was a groomer and he was a bad person.

On the 30th of January, 2023, after a week of ghosting, he told me he'd like to stop speaking, saying he was a groomer and a bad person.

After reading my story, you certanly will get/got an impression that this citizen is mentally sick (which he did not deny), he doesn't deserve to have a right to raise a child and he definitely must take the punishment, especially considering the fact that more probable I wasn't his first victim.

This story has likely given you the impression that he is mentally ill (which he never denied), and that he is misplaced to raise a child, and should indeed be punished, especially given the fact that it's unlikely I was his first victim.

I would appreciate a lot if you launch an investigation, and I would love to be informed in such case through email, which I'll leave in the end.

I hope an investigation will be launched; I'd appreciate if you could keep me posted by email. I'll leave mine at the end.

Also, I would very much advice to notice his girlfriend, (her name), because according to him, she was informed about our inappropriate conversations.

Also I would advise you to notify his girlfriend, who he told me was informed about our conversations.

However, he may have lied to me to make me think that it was normal.

There's a chance that he was not honest about this to convince me nothing was amiss.

Regarding the evidence, I've tried to download my data from Instagram in order to find my old conversations, however, it did not work out.

Regarding the evidence, I've tried to download my data from Instagram in order to find my old conversations, however, it did not work.

As the evidence, I can provide one lewd conversation and some of selfies which I still have (including Marie).

As the evidence, I can provide one lewd conversation and some selfies which I still have (including Marie).

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Since November, we stopped sharing nude pictures because of one accident.

Once, my father almost came across the fact that I used to take nude pictures, but I somehow I came up with a lie and he believed me.

Since that perioden, he started ghosting me, which led to decreame losing my feelings for him.

it isn't the right context to say 'decreasing'. it's better to say losing feelings.

On the 30th of January of 2023, after ghosting me for about a week, he told me that he wantsed to stop talking with/to me because he was a groomer and he was a bad person.

After reading my story, you will certainly will get/got anget the impression that this citizen is mentally sick (which he did not deny), h. He doesn't deserve to have athe right to raise a child and he definitely must take the punishment, especially considering the fact that more probable II most likely wasn't his first victim.

I would really appreciate a loit if you launched an investigation, and I would love to be informed inof such a case through email, which I'll leave in the end.

Regarding the evidence, I've tried to download my data from Instagram in order to find my old conversations, however, it did not work out.

As theFor evidence, I can provide one lewd conversation and some of selfies which I still have (including Marie).

In addition to this, we have texted on Discord for a couple of times, but unfortaneunately, I've lost my password.

However, I still have my account nickname and I can offer you it, in order for you to connect to Discord Support to get my old conversations.

I canould do the same for you with my Instagram (I know it's not formal, pls make it sound better).

It's alright actually. Pretty formal

I'm hoping you will take action and understake somethingnd my circumstances.

I don't really know what you were trying to get at here, but I rephrased it as a good ending

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Since November we stopped sharing nude pictures because of onean accident.

More natural

Once, my father almost came acrossfound out that I used to take nude pictures, but somehow I came up with a lie and he believed me.

Sometimes I tried to make up lewd conversations, but he mostusually didn't want to have them.

More natural

Since that period, he started ghosting me, which led to me decreasing my feelings for him.

On the 30th of January of 2023, after ghosting me for about a week, he told me that he wants to stop talking with me because he realized that he was a groomer and he was a bad person.

If this correction doesn't make sense, feel free to disregard.

After reading my story, you certainly will get/got an impression that this citizeperson is mentally sick (which he did not deny), that he doesn't deserve to have a right to raise a child, and he definitely must take ththat he must be punishmented, especially considering the fact that more probablest likely I wasn't his first victim.

I would greatly appreciate a loit if you launched an investigation, and I would love to be informed in such case through email, which I'll leave inat the end.

Also, I would very much advicese you to noticefy his girlfriend, (her name), because according to him, she was informed about our inappropriate conversations.

Regarding the evidence, I've tried to download my data from Instagram in order to find my old conversations, h. However, it did not work outI wasn't able to.

As theIn terms of evidence, I can provide one lewd conversation ands well as some of selfies which I still have (including Marie).

Made it a bit more formal

In addition to this, we have texted on Discord for a couple of times, but unfortaneunately, I've lost my password.

However, I still have my account nickname and I can offer it to you it, in order you to connect you to Discord Support to get my old conversations.

I can do the same with my Instagram (I know it's not formal, pls make it sound better)as well if needed.

I'm hoping you will undertake somethinge to hear from you soon.

Different meaning - sounds more natural. "Undertake" doesn't sound natural. You could write "I'm hoping you will launch an investigation on my behalf." if you want the same meaning, but more formal.