Every third image cannot be saved or exported

[FBM-PHOTO]

Every third image cannot be saved or exported - I get the error message - permission was denied - makes no difference if it is to desktop or hard drive - internal or external . 

[Chris B]

Hey FBM-PHOTO,

Can we have some info on your Mac hardware and system? 

Also, is Affinity asking for permission in Security & Privacy in System Settings?

It is odd that you can do it twice but not a 3rd time for each document. Do you save over an existing document or give it a new file name?