Bad customer service/ telephone etiquette

So I’ve been on the phone trying to reach myriad and they keep putting me on hold, I have made 3 contact attempts already which is costly as I hold hoping the currently busy agents will take my call but instead hand up. Please get your call centre staff trained and not to mute calls or hang up as these calls are not free!!! I need to discuss my mothers policy and you need to call me back, you had arranged to double deduct her premium since Oct and nothing had been done and we keep being told that she is behind with payments, that double deduction needs to happen this month or alternatively just give the details for me to make an EFT