Momentum Health´s Dental Department is not functioning

I am a member of Wooltru Healthcare, administered by Momentum Health. I have been struggling for more than a month to get a claim processed for emergency dental work which I had to have done overseas. I also need further dental work done and need pre-authorisation for this. I have sent numerous emails to Thelma Felix and all the other Wooltru and Momentum email addresses, including ***. All I have ended up with are a string of reference numbers, the standard meaningless email responses from some of the email addresses which don´t address my specific questions, no response from most of the other email addresses (including ***), incorrect feedback from Thelma Felix, a partially processed claim and no feedback whatsoever on the pre-authorisation. I have also tried to raise the issue with the Whatsapp number ***. After they tried to fob me off, they eventually promised that someone would contact me before the close of business today. No-one has called me. It´s so stressful to be sitting with expensive dental bills, invasive dental surgery, further work that still needs to be done and no support from the Healthcare scheme to which I pay a lot of money every month.