How could I restore it if the Facebook marketplace not working?

You could restore it after resolving Facebook marketplace not working. And, you can do this in a fruitful way. So, first, you are asked to submit this Facebook marketplace appeal form, and the support team reverts back to you within 24 hours. And after resolving this issue, you will easily get the Marketplace icon on the screen to buy and sell items. https://www.numbersupportcustomerservice.com/blog/tag/facebook-marketplace-not-loading/