SMS and e-filing documents show different amount

Got an SMS 'your 2020 year of assessment tax calculated results is - R5865. 71.' so I lodged in to accept when I view documents it shows a different amount - R1000and some cents now I wanted to dispute I couldn't system is always slow or freezing. Tried to call was caller number 1404 so ended up writing an email as I got paid the small amount as I was on the process of disputing the amount. Even the amount for 2017 on the documents is wrong cause I was quoted two amount ended up being paid the less one.