For over a year now I have not been able to do anything with Theme Store.
It tells me there is an update and it downloads and tries to install the update, but it always ends with the same message:
"Unknown error
An unknown error has occurred.
Try again later.
(-19)"

Is there a fix for this?

Thanks

 

Yes, there is plenty of space on the phone for the install and I have tried clearing the theme store cache, but it didn't make any difference.