Regardless of the reason your account was restricted, the only way to get out of this restriction zone is by contacting bet365's customer support. Even if you have no idea why your account has been restricted, you should still contact customer support to get an idea so you can open it back.

Check that you have sufficient funds available in your payment account to make the deposit. For reasons beyond our control, some card issuers may block transactions to gaming companies. We would advise you to contact your card issuer in this instance.