Have had my crown replaced three times due to its bad odor. Recently had a deep cleaning and it smells worse. What's going on?

Hello! I have a crown on my front tooth. I had the crown replaced about 3 times due to its bad odor. It’s so irritating and frustrating when the doctors don’t know what causes the odor. I went to see a new dentist two days ago she suggested to get a deep cleaning done. I gave it a try and I feel like it made the smell even worse. It’s been about two days since I got it cleaned. The doctor also said that she doesn’t see anything wrong with the root canal or my tooth. Can someone tell me what’s going on?