Duke Energy review: Monthly electric charges

I have had a solar system installed since 2018. At the start my monthly bill was around $12.00. Sometime in the future Duke was allowed to increase their monthly charge to $35.99. Starting in July according to a Duke representative the power generated by my solar system had suddenly decreased. In July I had net meter summary reserve over 1,000 KH. Since then the reserve has dropped to zero and their rep told me my system is no longer registering. I paid more than $250.00 to have a solar representative come to my home and check the entire system. That rep went through the entire system and advised me that everything was working properly and the electric meter was running in reverse. I spoke ro a Duke representative today and they cannot tell me why they are no longer registering any electricity from my solar system and could not tell me why my entire reserve has been deleted. In my opinion, Duke is screwing me and is probably doing the same to many others. My monthly charge is now doubled. I want a refund of their overcharges and I want then to refund the money it cost me to have the system checked.