If i were you i would just do it , with the flat screen now on the S24 they fit like a glove and if applicated properly you dont even know its there, and of course you have that little bit of extra protection and piece of mind
I also got the same message about invalid email, i called Samsung and they asked if i registered on tje Samsung website for the live event? If you didnt pre register then you wont get the voucher, thats why it says invalid email address
