Yah my grendes don't work any more and there 1 use now they run up close to where i tell them to throw it then nothing happens and it grays out. Same thing happens with sticky bombs and i know it's not they went out of range cause that problem was fixed a long time ago. This just started happing today with me.
You get one use for each gren squad and 3 uses for those with a upgrade make 1000% sure that you got the right squad.