Unhappy client

I had a payment holiday in December for my personal loan (advised by FNB this is due to ky account being up to date etc) Today A debt collection division called me to say I am in arrears.... Tried calling back.numerous times with no answer due to a lack of staff, spoke to advisor after advisor on the FNB chat bot and was first advised no one called me, then advised this was a error on FNB side stating the system held it back in error, now receiving numerous sms's stating I must pay immediately..... What the flip is going on.... no luck speaking to an actual person and now being threatened on sms that this will reflect on my credit bureau.