AWedding is today! Bride wanted fondant ribbon around entire cake!! Some of it is starting to come off! How do I fix this?? I've tried adding more buttercream but it's not wanting to stick

are these ribbons making up the border where one edge of the ribbon hits the board? 

or

are they covering the entire side of the cake? 

how wide are the ribbons?

don't panic -- stay cool --

your fondant might be too soft--and it might be too heavy--

maybe a little moisture on the back of the fondant--

where you brush it with water then wipe most of it off--

or a thin layer of piping gel if you icing is crusted nicely--

what do you mean 'added buttercream?

so how did it go?