When the name of a character violates rule 1 of the Tibia Rules, that character will receive a namelock. Because these are issued directly by customer support, there is no complain option on the account page.
A namelock only prevents the affected character from logging into the game and posting on the forum. Other characters on the account are unaffected. The reason for the namelock will be shown in the criminal record. You will have three chances to rename your character. The change must be approved by customer support, a process that may take up to three days. If a new name is rejected three times, the character will receive a random name from the name generator.
If you are certain that a namelock was not justified, you should contact a Tutor in the Help Channel or the forum. The Tutor will forward the case to customer support if he agrees that the namelock was a mistake.