This is yet one more idential situation of free no-deposit bonus taken (there's been so many of these cases already reported here in this forum alone!), whereby the player does not know, or did not know, all the relevant terms and requirements of that free bonus first!
It is standard practice for all casinos to demand and require a cash deposit BEFORE any withdrawal claim can be processed!
With crypto casinos, it can even be much worse - the player would be required to make ADDITIONAL DEPOSITS after that first initial deposit just to get the account fully verified and ready for withdrawal processing!
In so many such cases, they were SCAM! So BEWARE!!!