Mymtnmail Password Reset Issue

I have an email account with MTN which I created more than 10 years ago. Recently my account was hacked and somebody has been reading my emails at will. I tried to reset my password but I failed because there is no option to do that any more. Since MTN move email accounts to Zimbra, I think it was last year or a year before last, the option to reset password was deactivated. Then I checked MTN website and I found out that you call 135 to change password, deactivate email account etc. Yesterday, 06/04/2019, I called MTN support number 135 to ask them to help me reset my password the first lady I talked to told me to go to MTN store to reset a password because consultants were not able to change password. I told her that the nearest MTN store I know was 60 km away from where I lived, she insisted that I should go there. Actually, this store is 100 km away from my home, when I got there I was told to go to MTN Direct at Pietermaritzburg for a password reset, which is about 300 km away. I called 135 once again, this time I found a lady who was more than willing to help me, however, she could not since even on her system there was no password reset or recovery option. She asked me to hold while consulting her managers, when she came back she told me that two of her managers said they did not know Zimbra. Since my MTN email account was linked to Zimbra I should contact Zimbra myself to reset my password. Before I called MTN I visited Zimbra online help, they made it clear in their manual that if there was no option to reset your password you should contact your administrator, in my case it is MTN. Still my data is at risk and MTN does not care.