[joepie91_]

There may be some device on your network that's being abused as a residential proxy by "AI" companies, causing you to get caught in scraper block waves. A lot of sketchy mobile apps especially tend to bundle this kind of malware. Have a look at whether anything is using an inexplicable amount of bandwidth (doesn't have to be big, just bigger than expected).

[sixthDot]

What you describe cant be the reason because then the "access denied" would happen whatever the browser used is.