Grout won't stay. Dig out the silicone, clean the area thoroughly, and recaulk.

i caulked it before, but after time the silicone comes off.

Clean and recaulk is about it. What type caulk are you using? 100% silicone is the best. Next option if you do not want to keep caulking is to tear the shower out an rebuild it.

It also needs to be bone dry- I would assume at least a couple days between cleaning out the old caulk and redoing it.

Use alcohol - isopropyl 95,-99% ideally to also remove any soap scum residue - hinders a good bond to the tile and drain fitting.

i used 100% silicone.

i will clean and scuff it up better with alcohol, probably light sand the edge area before i caulk and see how it goes.

thanks

Make sure it is completely dry, as mentioned above a couple days sitting if possible.