AVAST PAY VERSION: MARK ALL INCOMING MAIL AS SPAM

Hallo

Avast pay version : 18.8.23565

Since about a week ago, all my incoming mail are marked as SPAM SUBJECT. It does not matter what type or what the address is. I thought it was my ISP, but it was not them. Then I had a look at Outlook, but could not find it there.
I then go into Avast’s settings and set the E Mail scanner to " Relaxed". It does not help.
All mail does have this *** SPAM*** in front of the subject although they are all delivered to Outlook’s inbox. None ended up in the Spam folder or the Junk Mail folder.
Then I stopped the E Mail scanner completely and everything was right again.
My question now is, what is the use of a spam filter ir everything is marked as spam anyway. It is of no help.
Is there a way to correct this or do I have to disable it permanently? Why does Avast give me something that I pay for and it does not work?
Regards

does this help? https://support.avast.com/en-ww/article/Repair-Antivirus

you may need to reboot after

Thanks for the reply.
I did what it said in the post and rebooted afterwards.
The problem is still there. If I turn off the Anti -Spam function completely, then it is ok.

Did you make any changes to the default settings ???

None, except the change of the Anti-Spam on or off

Follow instructions: https://support.avast.com/article/33/