read the box.
Don't trust any pc's listed, any advice or talks between posts on ID forums anymore , the Manips are let loose, especially the main one with 15+ accounts posting acting as different people.. do your own research
Except that I have this problem too and my inventory is completely empty, and there's 70 free spaces in my bank.
Kings Eastwood in
THE
GLOOP
, THE
BWIAN
, and THE
WIKI
music by Trewavio Morricone
The game checks if you have enough bank space to store the initial protean box (that everyone rolls).
However, in F2P, it counts differently. It checks whether:
F2P items banked + P2P items banked + space for claiming <= F2P bank space.
The problem is that P2P items are taken into account in this calculation. The only solution atm is to reduce your bank space such that F2P + P2P < F2P bank space either through temporarily dropping / trading your items. Claim your reward from TH once it's lowered and return your items.
You'll have to do this with every TH roll though.
Why Jagex hasn't patched this known. and especially, a Treasure Hunter bug is unknown. Oh well, their loss for their revenue.