Cut off No Warning!

Been a customer of MTN for over 20 years. Always paid my bills on time, Always upgraded with them and supported them... got cut off today!! No warning, no email, no statement... just cut off!!! I called to ask what the hell and was told I short paid this month by R54!!!! Are you kidding me?!?!? Over 20 years a well paying loyal customer and then they cut me off for an amount like that?!? Don't even get a warning??? Greedy and disgusting... they don't care about a damn thing at the end of the day except R54!!! I am moving to another service provider immediately... what does loyalty and goodstanding get you? Nothing! Bye MTN!