"Train as Good" no longer moving the message to the inbox

Hi,
I’m on an iMac Pro with macOS 11.2.2 and SpamSieve 2.9.43.
What worked for over a 15 years now has stopped working: “Train as good” no longer moves the message to the inbox. The message shortly disappears and then reappears in the spam folder, without “spam” background color but still with a brown font. This is the log:
===================================================================== Trained: Good (Manual) Subject: Top Golang IDEs for Go developers | Setting up a Mac for development From: notifications@emails.tabnine.com Identifier: WEO7AZrLT3SKF5XXN2N/ug== Actions: already in Good corpus (7169) Date: 2021-03-04 13:00:17 +0100 (GMT+1)

Junk mail filtering is disabled in Mail’s preferences.
Thanks for the help!
Jan

Are there any other computers or devices accessing this mail account?

Apple Mail in Catalina and Big Sur sometimes isn’t able to move messages from one mailbox to another. Often it works better if you use a Spam mailbox on the server so that when you train the message as good it will be moving back to an inbox on the same server.

Are there any other computers or devices accessing this mail account?>

It seems my MacBook interfered. The lid was closed but I guess Powernap did something in the background.
Thanks for the quick answer and can I mark the thread as resolved somehow?

Glad you figured it out. You may want to turn off the relevant Mail rule on the MacBook to prevent that from happening. Writing that the issue is resolved is enough, thanks.