ok pierre i have just had the same trouble and fixed it as follows
1. on main screen ( the one that plays music ) and you select the game you wanna play
2. select change equipment
3 along the bottom you will see a tool type bar its says BAGS, METERS DRIVERS etc
4 if you have a stand bag drag it under your profile picture ( if it is not there in the first place) and save changes
5 it may as mine has up to 4 different sections go to each section in turn and if the club/s you want to sell is there. if it/they are make sure you unequip them/it.
6 this error is wgt's way of saying you have got stuff equipped
Hope this helps as it cured my problem