Recently I was working on a quick one-off project. I found a WordPress plugin called Support Tickets that pretty much did everything that the project required. The last time I touched php was nearly a decade ago so it’s not my usual bag, but it works, so why bother being snobby about the technology used?
Late in the game a few issues cropped up, I managed to figure them out and fix them. Looking on the support forum a few people are using it and suggesting all sorts of fixes.
I hope it helps.