The forum is seen by Fairphone as a place for discussion amongst customers and/or people interested in what Fairphone is doing. They don’t see it as a support channel. The community moderators are members of the community, but not Fairphone employees. So things like returns cannot be handled through the forum (we have no influence over any of that).
Fairphone customer support can be found via https://fairphone.com/support. The easiest way to file a support request (which is the first step towards returning the phone for repair) is via the support form. If it’s urgent, consider calling - call details are at the bottom of all the support pages (including the form), between the ask a question button and the grey footer. For more forum tips about Fairphone support, see this guide.