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.
Step 1: Contact the Bet365 call centre and formally ask for account activation. Note that Bet365 can treat this request only if your self-exclusion period has ended. Step 2: Once the betting operator has handled your request, you'll get a confirmation email. Click on the confirm button to activate your account.