I brought the disc copy of FF14 but I'm having trouble. A message comes up after I enter my username and password

"No valid account is avalible to play FF14"
"In order to play FF14 you must first purchase the digital download and register a product code"

"Please restart the client for FF14"

I have the disc based copy and I have a SE account but I keep getting this. Can anyone please help with this issue?

Thanks in advance