casino says my blackjack session needs review because i kept same stake for hours

Played a long blackjack session online last night, kept my stake exactly the same, literally not changing my bet at all for hours. Got an email this morning saying my account is under review due to "unusual betting patterns" and they're holding my withdrawal. I checked their terms and don’t see anything about flat betting being an issue. I’m really careful about promos and T&Cs in general, so this is kind of irritating.

Not sure what to make of it. Has anyone else been flagged just for sticking to a single bet size? Did you end up getting paid out in the end? Wondering if it’s worth pushing back harder or just waiting this out. Any advice on how you guys handle this?