Invalid Voucher

I am appalled by the service I received at MTN customer services call centre . I bought an airtime on the 06/03/2023 at woolworths and everytime I recharge it says "invalid voucher". I have called customer care every single day from that day and till now I haven't gotten any assistance to date. I have spoken to a number of agents who rudely told me that they will not be able to help me. Yesterday I spoke to one of the 'Supervisors' who in a very rude tone told me that my matter will not be ascaleted and I'm not the only one having this issue and I must go back to woolworths with the voucher. The name of unprofessional 'Supervisor' I spoke to was Leviya Makena from a Gauteng call centre who also very eager to correct my engish grammar while on the call. I am disgusted and appalled by the service I have received to say the least. I would like all the calls I have made from the 6th March to be listened to and my grievances to be attended to immediately.