Contract term date

I took out a contract with MTN on 03/01/2023 for 24 months, even on documents I receive it state that its 24 months, I noticed when I check my invoice, I send them an email disputing it, and I send them documents, I was told to go to MTN store I took out a contract with .I went to the store I was told the person who was assisting me no longer works there and there is nothing they can't do; I also send email to MTN complaints they didn't bother to assist .