Dental Work

I am currently under private dental care because I couldn't find any local or nearby dental practices, which offer dental care to NHS patients or private dental patients. I can barely afford private care, but I had to pursue it because other dentists are full and it was 5 years since I visited a dentist at the time, so I decided to just go with it for a while. I had a checkup and a dental cleaning at the dentist, which both were very expensive, I already paid for the checkup, not the dental cleaning, but I just had it today, but I feel like they will ask me to pay after the full course of treatment of teeth is finished, which I am only due to pay for the dental cleaning at the moment, which I can pay for and will pay for, but they also recommended fillings, but they are too expensive, so it would be better if I could try to find an NHS dentist practice again, even though I have failed multiple times, I need a total of three fillings, which of course is a lot of money, I don't want to leave my dentist, until I find a new, NHS dentist. I'm not even supposed to be paying for dental work, because I am entitled to free dental care, but as I am a private dental patient, it means I cannot not receive free dental care and it wouldn't matter anyway because my exempt letter is set to expire this month, anyway. I would probably still struggle to pay fot NHS dental care, but at least it is way cheaper than private dental care, I honestly don't see the difference between the two, anyways. I waited 5 years to go the dentist, simply because I couldn't find one, I can't wait any longer, especially if I need fillings. Any advice? I live in Longsight and majority of dentists in my area or nearby areas are oversubscribed with NHS patients.