Soak and water doesnt always work because first if you dont dry it scrupulously afterwards then any remnant spores will just grow again; added to the fact that most golf bag materials these days have very fine texture that spores can get into. To kell mould you just need to get rid of eth dampness, and then remove teh spores (or just make sure it doesnt get damp again, but that's not always easy with a golf bag).
Had this happen to me a couple of times - what to do
Empty the bag of everything
Bring the bag into somewhere you can leave it to dry - perhaps the airing cupboard;
Srunch up several newspaper pages into balls and stuff into teh offending pocket (but dnot stuff it full)
Leave for a day or 2 until you can be reasonably certain that it has dried out.
Then get a stiff brush and brush the insides of teh bag where the mould was (not so easy depending on where
At that point you can try the Miltons fluid (or whatever) but again make sure it is dried out fully afterwards
)
