Yes it could be that your account is brand new and you have some sort of restrictions because of that.
From the link crairezx20 posted it says:
Not new to Facebook: To prevent fraud, accounts that have been created very recently can't access Marketplace. If you recently created your account, check back later to see if you have access.
https://www.facebook.com/help/www/972392066266648?helpref=popular_topicsIt doesn't say how much you have to wait though.
EDIT: After a search it seems that many people are affected by this and even older account. Users complain they can no longer access the marketplace even though they were able to do so sometimes in the past.
I managed to find a tip how to get it to work from a phone, try it out and let us know:
So I found out how to access marketplace -
From my phone only, not a computer
-settings and privacy
-settings
- access your info
- marketplace
- click items sold or items bought
- click the following option
Now I can search the marketplace. Try it and see if it works for you.
Source:
https://www.facebook.com/help/community/question/?id=10211088326346952