Europcar late invoice and deposit hold up.

I booked a car and returned it on Tuesday the 24th of December 2019. Reference *** I then picked up another car at the Mthatha airport on the same day which means I have more 10s of thousands tied up in rental deposits at this time of the year. When I spoke to Velly, he assured me that my deposit would have reflected by yesterday already. I call in this morning to be told my invoice was only done THIS MORNING the 31st of December. I booked a rental with bidvest which was returned just a day before I booked with Europcar and Chantelle arranged for my deposit refund to be authorized within an hour of my request and I had also used a debit card with them too and it was no hassle as they understood my situation. I need the money asap for emergencies and I am told I have to wait until Monday the 6th of January to get my deposit. Whose fault is it that I was invoiced only a week after dropping off the car. Holidays or not this is unacceptable. I am never using this brand again if this is the service they give. They say "nothing can be done" but their competition has proved that nothing could be further from the truth. Why do we have to wait this long to access our money anyways when it takes a minute to hold it off our accounts. No amount of policy schooling can possibly make me understand that part. I want...no wait, I need my money as in the yesterday it was promised.