CentroDent asking me to pay extra even after the payment

I have been contacted by CentroDent, the dentist in Bern. I got the root canal treatment done in June. The first day, the dentist told me the two choice; either take out the tooth for less cost or do the root canal with 50% success rate for over 1000CHF. I took the second choice as extracting would cause more problems like the teeth form. The dentist made the estimation on that day, and I paid the entire fee.

I visited the dentist 2 times more for the treatment. As I paid my fee from the credit, they did not ask me more.

Somehow, they contacted me and asked me to pay about 390CHF. I have already paid about 1100CHF at the first day as the credit. I really don't see what makes me to pay that much even after paying the full estimation cost. The problem is that I paid the fee by cash, so I cannot prove my payment from the

If it is in Hungary, you probably get a cheep crown for that extra payment. I really don't know what this overcharge is about, but Ms. Kukeli asking me to pay... Yeah, 386.26CHF extra to CentroDent for whatever the reason. If you are asked to pay extra fee from your dentist even after you paid the bill, what can you do? I really should not pay the bill by cash, or I could have the receipt from the Post Office as the evidence.

Be aware of the Swiss dentist asking extra charges even after paying the bill from the estimation... This is my experience with the Swiss dentist.