Release of "Hold" on Credit Card not being instructed to the Bank

Sadly the inititial good experience of super helpful staff at Hoedspruit has been severely marred by the fact that the "hold" on my credit card took 2 weeks to clear, and then for no reason at all another "hold" has been slapped onto my credit card the day after the first one was released. No explanation for this can be given to me and having requested the finance department to phone me, I still await the call. Definitely will NOT use this company again. I have used up so much time calling them and the bank. Credit must be given to Goodenough at Hoedspruit for his politeness and attempts to get this sorted. Obviously his finance department has let him down. The car was handed in and all cleared that there was no damage - the rental fee came off my credit card virtually immediately - so WHY can you not release the "hold" amount. ??