Insurance dragging their feet reprocessing claims denied in error

At the beginning of the year I received several EOBs for health insurance claims that were denied, stating they were denied because they occurred after my coverage had ended. This was a clear error as I had active coverage at the time of the claims and still do. There was no lapse in coverage anywhere close to the time of the denied claims, and I have had similar claims paid out both before and after the denied claims.

I initially called when the first denied claim came in and figured out that the claims had been processed under an old “profile” (not sure what else to call it) that was inactive rather than my current active profile. Essentially I had previously been on my wife’s insurance for part of 2018, came off it for the rest of 2018 and 2019, and then got back on the same insurance from 2020 to now. The member ID numbers did not change, and somehow my insurance processed several claims under the inactive 2018 profile rather than my active profile. They have since told me they have removed the old inactive profile from my record to prevent future claims from being processed under it (and so far the error hasn’t been repeated since February or so). But since the ID numbers were the same, it seems to be a problem on the insurance side, not on how the provider billed insurance.

Since we figured out relatively quickly that the claims were denied in error, they assured me that the claims would be reprocessed. I was told tickets were created and sent to the appropriate departments for reprocessing (and I got the ticket number for at least one of these). However, I haven’t seen any signs of progress in reprocessing these claims in about 3 months. I first called about this in late February and I followed up at least two additional times, most recently in mid-April when I received the EOB for a second erroneously denied claim (for >$5000). I was told claims could take up to 30 days to reprocess but it’s clearly been longer than this.

I plan to call again this week to check in on the status of these claims that are supposedly being reprocessed. But I haven’t seen any evidence that they have been or will be reprocessed. What are my best options for ensuring these claims get paid if insurance continues to drag their feet on fixing something that is clearly their error?