Hello,
Start from checking out the following articles:
Enabling the Invite Banner on the Mobile Version of Your Site
Removing the Wix Banner Ad and Favicon
Removing the Wix App Banner Ad from Your Mobile Site
If the articles above do not help you, please try contacting Wix Customer Care as they know best.
https://support.wix.com/en/article/contacting-wix-customer-care-for-support