Just after this spring vacation, my university department was going to havehaving an exam held face-to-face. Just after spring vacation, my university department was having an exam held face-to-face.

However, the situation ofbecause COVID-19 in my prefecture is getting worse, so the test will be prolostponged. However, because COVID-19 in my prefecture is getting worse, the test will be postponed.

Prolonged is when something is already happening Postponed is when something is put to a later time

I'm happy that a white elephant disappeared, but I’m unhappy the next semester's classes will be online. I'm happy that a white elephant disappeared, but I’m unhappy the next semester's classes will be online.