Opportunities filter won't clear

Hello. We are using version 7.12.6. In the Opportunities module there is a strange behavior. We can filter opportunities normally, but when we try to clear the filter, one rule always remains. No matter how many times I click on the X to clear the filters, it reappears. I have already done a Quick Repair and Rebuild, cleared the cache folder, but it didn’t solve the issue. We bought the “Opportunity Line Item” module, but that was over a year ago, so I don’t think it’s related to this problem.