[Chimera-users] Fc dimer fall apart after fusion with a GS linker

Dear Ms/Mr helper: I encounted an issue when I try to fuse one (G4S)x linker to one of the Fc "C" terminal using "join bond". Once selected the "C" atom on Fc C terminal and "N" atom on (G4S)x N terminal and hit "apply" button, the Fc dimer fall apart but the (G4S)x linker was connected to the C terminal of Fc. How to avoid the Fc dimer from falling apart?  Thanks very much for your help Sincerely  TW