Can’t link digital Suica card (iPhone) number to Shinkansen ticket purchased on eki-net

So I bought Shinkansen e-tickets on the eki-net JR East site. I also bought and loaded new digital Suica cards on my and my wife’s iPhone. Now I can’t link the Suica card numbers to the Shinkansen ticket. The Suica card numbers, found in the Suica app, start with JE and have 15 numbers (and some letters) after. The field only accepts 15 characters. I get an error every time I put the 15 characters in (without the JE; I read somewhere to take the JE out): “The specified IC card is not accepted. Please register a different IC card.” What am I doing wrong? Thank you for your help.

by achtbaan66