Not sending not receiving emails

I have eM Client since mid May. Since 2. 6. stopped to send emails and since 6.6. stopped also receiving them. I did not change anything in my notebook. Than I was in hospital and after returning to using comp now it is the same - eM Client does not work. The error message on both, POP3 and STMP, is: “Attempt to connect failed. It may be temporary inaccessibility of server or wrong setting. Do you want to check settings?” I have checked everything, I really do not know what to do. I have disabled also antivirus programe. Does not help. I have reinstalled eM Client, does not help. I have renewed free licence, does not help.
Please, what to do?

If this is a Gmail or Google Workspace account, see: Google ‘less secure apps’ access and what it means for eM Client | eM Client