First of all you need to remove all your logos from your account.
Open the Account Profile page and click the Remove Account button.
The account removal request will be sent to your email.
You have to click the provided link in email, which will redirect you to the final step. Confirm the removal of your account to completely erase your data from LogotypeMaker.
Once the final step is completed, your account will be officially removed and you will no longer have the access to your logos. However, you will still own the custom logo you’ve created and downloaded.