Had exact same issue, didn't receive the letter supposedly sent in Jan, subsequently no payment forth-coming in May. Lady at DWP said it's OK, she'd cleared it and Jun was fine. Don't know if I'm expected to do anything now until next year ! Somewhat annoying as I only became eligible in Dec last year !
Oh , it's no different to amending road traffic laws .Bt 2000 for not wearing a helmet, only enforced in major city centres or tourist areas. Very few cannabis shops outside of those areas and Thais will "go back to " what they've always done...just like riding their motorcycles illegally.