If you have an entry ban to Turkey, you must learn the reason and then appeal the ban decision to revoke the ban.
Travel Ban on Entry into Turkey: How to Revoke Entry Ban
Entry Ban Notification Form: Restriction Codes’ mean and how to appeal?
When you have an entry ban you will get a restriction code which describes the reason of the ban. Which restriction code is given for which case?
The Consequences of Overstaying 90-Days limit in the European Union
Overstaying 90 days in the EU may lead to fines, entry bans, and deportation. Future visa approvals can be affected, and re-entry restrictions may apply across the Schengen Area.