Can't Register Photoshop Elements 2021

[daveh87663010]

Was running trial version then purchased PSE 2021 at big box store. Obtained s/n online using redemption code. Entered s/n in program - no problem. Tried to register product in my account using s/n. Get a message: "this serial number already in use." Spent an hour on Adobe chat - no help. 

[Peru Bob]

You may need to contact the big box store.