Referall Codes not working

I have some codes in my email but all of them return this error and I defo havn’t used them yet:

‘This code did not match any active discount. Was it entered correctly?’

Copied straight from the referral page too.

I think you must try with a code from your own country. Where are you from?

what do you mean? They are all just sent to me via refer-a-friend@mention-me.com

I have been using them in the past just fine but today it wont let me enter any.

Am from uk, but these referrals don’t seem tied down to a country.