Money not allocated

My name is Nwabisa Ntsiko ID No ***. On 14 AprilI reversed the instalment for my 6 month loan and Mobi Money and on 16 April I did an EFT transfer of R3100 to cover both instalments and to my suprise only R1480 was allocated to the 6 months loan and the rest is missing and when I called the company to enquire about that they advised me to send the proof of payment which I did an I called them again and they said its been allocated but now everytime I check their app it still shows that no allocation was made and that the accounts are in arrears and when I call it seems no one knows when the allocation will be made but on 27 April they called me saying the allocation was done and the accounts updated which is still not the case. I have been using my airtime to call them and have thus issue sorted as it is now affecting my credit rating and score but its seems like no one in yhe company is willing to assist me and I have been doing follow ups since the 26 April.