So i went in for my appointment last friday & the girl said that was fine & that I passed the requirements & I thought she said that the payments would be in the Post office on the 21st, but what I didn't realise (until I got home) was that the 21st was Saturday. Did I just hear her wrong or could it just take one day for the payments to be sorted?
I think either she has got her dates mixed up or you have heard wrong. You can do two things, you can try to contact them (which depending on the office may or may not be difficult) or you can go down to the post office today and see if there is a payment waiting for you or one due in the next day or so. If you go down and there isn't one there, then you'll have no option but to contact the office or go down yourself again.