FedHealth Pre-Authorization Nightmare

PreAuthorization was approved by FedHealth in 2016 at Linksfield Hospital. When leaving, it was advised their was no outstanding amount by both doctor and hospital. Many months later, Linksfield Hospital had emailed a massive statement to say they had not received payment. Then again in 2019, preauthorization was again approved for a procedure at Sunninhill Hospital, same story again...but this time they at least gave us a reason. Apparently the membership was inactive since 01/07/23019 (apparently that is the year they state). No response from emails and calls not returned. How can you give someone preauthorization and then months later have the hospitals send you emails to say your preauthorization was declined?