Atmos Financial PBC review: Solar financing

I contracted with EHS for solar panels and they processed financing through Atmos Financial PBC. The interest rate was 5.55 which I thought wasn't bad, although my credit scores were in the 790's. The panels were installed in after a new roof was installed in May 2023. Atmos started billing in June and the frist payment was $145.82 and was applied as 80.43 interest and 65.39 to principal.

The next payment was 7/7/2023 and applied as 106.92 interest and 38.90 principal. Next was 8/7/2023 applied as 110.31 interest and 35.51 principal. Next was 9/12/2023, should have been 9/7 but there was an error with Atmos automatic withdrawal from my checking account, but I have a text saying that they would back date it to 9/7, and was applied as 127.90 interest and 17.92 to principal. I had many contacts with Atmos during the end of August and the beginning 10 days of September because Atmos hadn't taken money from my account. After the September payment I again contacted Atmos as to why it wasn't back-dated as was texted to me, and why was the interest payments increasing and principal decreasing payment after payment. I was put through to Pete Hellwig, founder of Atmos and he explained to me that my account was funded by Five Star Bank and that the applications of the payments were correct. I called Five Star Bank and was told they indeed had my account but they could not discuss anything with me because of their contract with Atmos. In all my life, with many loand and a couple of mortgages I have never seen interest increase and principal decrease. Although Atmos says it is not a bank, they withdraw $150 monthly from my personal checking account here in Florida and apply it to an assigned Atmos checking account, which is then sent to Five Star Bank. Something isn't correct with this account. Please advise