At the plymouth game I had west brom showing,my son had plymouth.
I phoned the club up who told ne nit to worry as the barcode would still let me in.
I asked for an email ticket just in case and lo and behold it wouldn't let me in,so I used the email.
I was behind 2 other fans who had the same issues and they were told to go to the ticket office!
Apparently it's because I have a Samsung phone! My son has a Samsung and not had a problem