Second probably unrelated or unhelpfull idea. Has your antivirus program been updated and any extra checks added. I noticed when haveing a google that there had been problems with vunerabilities in many routers.
https://www.welivesecurity.com/2020/...ecurity-flaws/
I will now dissapear as I notice there are a couple of members watching this thread and I don't want to make a spectical of myself in front of an audiece.