vodacom negative credit bureau reporting for 1 day late payment

vodacom will report you to experian even if you pay your account 1 day late.my credit profile with experian shows 1 month in arrears with vodacom even though im up to date with all payments.i probably paid them 1 day late or at most 2.so they report me to experian and negatively affect my credit record.I will be cancelling all my remaining 3 contracts at the earliest convenience.this is how they treat customers of 30 years plus.