We searched about it on forums and found out some sites decide to ban players when they win.
Now the support is saying that my account got frozen because of multi accounting.
Was it illegal to open two accounts between me and my husband?
The main problem here is the IP, since you and your husband were on the same IP, that looks like multiaccount.
Casinos don't ban accounts when they win, the first look for an excuse to ban it, and 2 accounts on the same IP is a justified reason to block your account. I know it sucks because with KYC you should be able to prove how both accounts was from different users. But the stake support is really hard to deal with nowadays, i stop using the site because they ban me from the chat for 6 months. And even if i talked with them and told them it was a mistake they decided to hold the ban. Usually, support should give a warning to the user before a 6 months ban, but they have their politics about how to deal with users. From my point of view it was a rude move and they lose a customer.