Yeah, that happened to me with BetAnySports. Won like $25k over 2 months, then they limited my live betting to $25 per game. So I went elsewhere and promptly lost $10k.
It's crazy! Some books you can't lose at, others you can't win at.
I get limited at BetMGM, every time I went to bet, it takes forever and rejects it and gives me a smaller amount. Like if I tried to bet $1050, it comes back with $802.48, random numbers. I called my rep and he told me. I said I'm done playing there