I found a work around, I refunded the Mission Gold Pass in the Swap shop. Then I went to the Mission Pass Details and redeemed the gold pass by claiming the rewards in the Gold Ticket section. A strange workaround but yeah...

I also have this issue as well, I just reached Tier 30 Over run and it won't let me use the Mission Pass Gold Ticket for this season. Whenever I try to use it, nothing happens and the ticket remains in my inventory as if nothing has happened. I also tried using it in the mission pass and it would give me a message saying, "An unexpected error occurred."