Harrasment!

I short paid in december due to lack of a invoice which was only receive 3 jan. I then oaid tge short amount of R36. Since then i have been geting upward of 60 automated calls a day on my cel . Its is interrupting my word and is harrasment. I have phoned everyday and keep getting the same explanation. Technical error. I am now getting call on ALL 5 MY VODACOM CONTRACTS EVERY 30 MIN. This has to stop!!!