Balance owing but received paid up letter

Good Day

I paid my JET account through to MBD, they emailed me paid up letter as a proof that account is paid in full, so last month I received an email from Nimble Debt Collectors stating that I have a balance of R330, I sent them my paid up letter, yesterday Daly Attorneys sent sms and called stating I have R333 outstanding balance,

May you please advise what to do now because I'm now confused, one minute account is paid up, one minute I'm still owing?