Trial license canceled after a short time

I activate the trial license for training and after a short time it is canceled and asks to enter the activation key again. What can this be connected to and how can I solve this problem?

@Vlad_Svitelskyi

I believe you have activated the Enterprise License, Either you extend it with the new license OR

Remove the existing version and
Suggest to install the Community version as your requirement is to for training only

Community version is free and never expire

Thanks

I activated the Automation Cloud license, but after a few dozen minutes I was asked to enter a new license key again