Avis car rental doing ********** transactions

Our insurance company used avis car rental kempton park for our courtesy car when my wifes car was being repaired. I paid a R1500 refundable deposit on collection that was supposed to be paid back to me on car return. Avis deducte R306,32 the 11/05/2021 for etoll "after we were not informed of the etoll charge" I then went to see them,where I was told that they will escalate it for me and ger back to me,which they never did.They again deducted R253,08 on 03/06/2021 for etoll and R1708,17 "for hell knows what".The car was returned 28/05/2021 with a full tank of petrol and clean.......they said that the R1500 deposit will be paid back to me within 7 days after car was returned,instead of paying the deposit back they deducted R1961,25 this month. Can someone please help me,aa fnb said they cannot help me,coz it was not a debit or but a card transaction. I have tried to contact avis several times,and each time they said they will transfer me to the relevant department and then after about 10 min's of holding on the line,the phones cuts. Avis car rental is committing ********** transaction without people knowing or authorizing the trnsactions......I did not even get so much as 1 single invoice for on of the 3 deductions made from my account,they just deducted the funds. It is ridiculous and disgusting that Avis car rental just take funds off my account as it pleases them without any autherised communication from me,and even more so that FNB just said they cannot do anything to help me "especially the fact that I am a Private Clients account with FNb"