Managers error and not apologetic

Went to Donna Clearwater because a shirt I bought at Donna Maponya mall was small and they had no other sizes. The cashier checked and confirmed that Donna Clearwater had the short. I went to Donna bought the shirt and so much more. Cashier Jabu gave us customer service that was exceptional and after confirming that a certain pair of shoe is available at Foschini, I went and indeeb bought a pair there. As I went back to thank Jabu I decided to buy two more pairs of shoes where the store manager actually performed the sale. As I got home I realized the store manager overcharged us with R140. 00 I called the store and confirmed the error and adviced that I could not correct this error in any near store and have to come to Clearwater mall to correct this. On the call I stipulated that I'm holding them liable for this error and want to be reimbursed for the transport getting there. The lady said ok. I went to the store today 11 Feb 2020 the manager was not in store, Jabu the cashier performed the refund and called the manager for my transport reimbur*****t and the manager merely did not help and said I should have performed the correction at the nearest Donna which was not the information I was advised. She also said she would call me the following day when in office to sort it out. Jabu reinbursed me from her own pocket for the inconvenience I received all because the Manager did not check my parcels and overcharged me the first time. Why must the cashier be the one resolving her (the managers) error?