CCC Overpaid by next

[olhuxo]

Hello, I left next in august 2019 and have now received a letter from CCC stating I was overpaid by £85.85 by next from taking holiday hours? . The working month goes from the 14th to the 15th of the month and I left around the 24th of August. Even though it is not a lot of money I'm at uni and no longer employed I just work the odd shift on the NHS agency when I get the chance as my course is full time and requires 40 hour weeks on placement that are unpaid. I already did not get any wages for september even though I worked after the cut off date 15th-24th. I feel like it is more than I expected to pay back as i was expecting a small wage in september which I automatically assumed they would deduct anything necessary at this point meaning I would get nothing. However, it has resulted in me getting no wage and also a £85.85 repayment charge as well. Does anyone have any advice on who to contact to get this amount checked with a breakdown as the CCC have been no help and next HR wont speak to me and require my manager to call through the shops phones which is impossible to do as he is always busy.