Sorrry, it should be easy, but I don't find:
How to change the MainVendor in VM3?? It seems to be connected to one user - which does not exist anymore. I try to change but get always the message "this user already exists" or "this email already exists" - of course they exist. I need to change to the superAdmin for testing, and changing back if everything is well?!?!?
But it seems not to be possible?!!?
enable the Tools in the VM admin->config
then under Tools & Migration->Migration tab there is a Set Store owner
enter the Joomla user id