I have received a message saying

You have been found to be related to an account beginning with Just customise - I am just customise so not sure what is happening ?

my account has been deactivated and I have to prove that I don't have this other account but I don't even know where to start, there is no email giving relating to this other account. I didn't start another account in the past, I have only ever had this account.

The only thing that recently happened is Amazon have added me to other Marketplaces.. Could this have caused the issue. Really need som advice I don't know where to go with this..

Thanks in advance