As we spokediscussed on the phone;,

The execution process between BV Australia and Daniel Guerci is still ongoing under Rome 16th Execution Office with number 2017/10633.

Consider combining this with the previous sentence: "As we speak on the phone, the execution process between BV Australia and Daniel Guerci was still ongoing under Rome 16th Execution Office with number 2017/10633."

The total debt is made up of main debt (137.,686 EUR) , interests and expenses.

English uses commas, not periods to divide numbers

On the other hand, 30.,000 EUR of the debt has been paid up to now.

Consider an alternative phrase here, "However, 30,00 EUR of the debt has been paid as of today". The phrase "on the other hand" is usually used when comparing two options or choices.

Mr. Daniel has been retired and got his severance of 75.,000 EUR.

Consider changing this sentence to "Mr Guerci has been retired and recieved his severance of 75,000 EUR".

He wants to close a couple of execution processes related to him.

As a result, we want to close the execution process between BV Australia and Mr. Daniel by paying 75.,000 EUR.

We would be happyappreciate it if you would help us out aboutwith theis matter by gettallowing us to communicate with the company’s decision makers.

The phrase "getting us to communicate" implies that you are trying not to communicate, and they are going to have to force you. Consider rewording this sentence to "We would appreciate it if you could help us in this matter by putting us in contact with the company's decision makers".

As we spokediscussed on the phone;,

Tthe execution process between BV Australia and Daniel Guerci is still ongoing under Rome 16th Execution Office with the number 2017/10633.

The total debt is made up of the main debt (137.,686 EUR) , interests, and expenses.

In English numbers of this type, we use commas instead of decimals. Correct usage examples: "I gave him $137.00." or "I had to pay 1,000 euros to get the car fixed."

On the other hand, 30.000 EUR of the debt has been paid up to nowto date.

Mr Daniel has been. Guerci retired and gotreceived his severance of 75.,000 EUR.

I'm assuming "Guerci" is this person's last name / family name. With "Mr." people generally use the the last name / family name. Also, remember to use a period after "Mr" since it's an abbreviation for "Mister."

He wants to close a couple of execution processes related to him.

I'm not certain if this particular correction is the best, since I don't fully understand the matter you're writing about. Sorry. But I can share that when you are talking about more than one process, you should use the plural, "processes."

As a result, we want to close the execution process between BV Austalia and Mr.Daniel Guerci by paying 75.,000 EUR.

Remember to end sentences with a period.

We would be happy if you would help us out aboutwith theis matter by geputting us to communicatein touch with the company’s decision makers.