Yeah, the provider line isn't always going to have correct or helpful info. What is the actual denial reason code on the claim?
Were the diagnoses coded correctly? This denial can be when someone makes a mistake with the last digit of the diagnosis is incorrect. Like, someone accidentally coded a laterality conflict. They coded RT diagnosis when it was on the LT side and you have a LT modifier but the dx says RT, for example. You could change around the modifiers all you want, but if the diagnosis does not match it would still be denied. Or, the payer is stating it's a modifier issue when really it is denying for some other reason.
Other than that, I would have to see the op note and what was billed (redacted).