The guy on your other thread already answered you (edited a bit)
1. It may not be approved yet (Staff are not 24/7 active...) (May take more time than told if there's more verification to do idk)
2. If it has it might have been deleted - check your private messages
3. If none of the above, click on your user, go to your profile and look for your latest threads under your profile pic.
4. If all of these steps did not work you probably failed to post your thread.