One thing you should never do is delete maps manually.
That will cause all types of problems.
Do Not go to the folder SDCard\Android\com.tomtom.gplay.navapp\files\data\ maps <------DO NOT DO THIS !!!!!!!!!
Repeat: DO NOT DO THIS
1. Go to settings
2. then Maps
3. then Edit List
4. then pick the map or maps you want to remove
That is the only way to do this.
Then you can add new maps after the map has been removed.
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