I am a user with avast antivirus free. While I was away for a while, AVAST detected some of the configuration files of the program I used to scan for malware as viruses and popped up a blocking message. I don’t remember requesting the scan. I did restart Windows File Explorer to scan for malware, which caused the antivirus to restart and do a scan on its own. It identified the file as a threat because of idp.alexa.54. Does AVAST often perform uncommanded scans like this and automatically alert me to threats?
Have you double-checked that no automatic scan, including smart scan, has been set?
Furthermore, it could also be that a process started automatically and that Avast detected it and blocked it, assigning it as malicious.