I've used a number of glue sticks, both white and purple, brand-name and store-brand...my only criterion being that it said "washable."

I don't know how you washed out your glue stick, but this is my method. After my applique is complete, I soak the block in a big bowl of water for about 2 hours. If I'm in the vicinity, I give it a squeeze now and then, and maybe change the water if it's looking cloudy. Then, I air-dry the piece before pressing it. I've never had any of the glue show up again after treating it this way. Hope this is helpful.

Oh, I never heard of that. What brand was it?

Hi quilterba and welcome to the forum. I am wondering if the glue was a fabric glue? I have found that some glues do not go away, and it's always on a very pale coloured fabric that it is noticeable. I have no suggestion for a fix but maybe somebody else does. Do you have much of the project done with the glue or could you start again?

I used a washable glue stick on a very good quality of linen. Now every time I iron my project it keeps popping up.
I have washed it with gentle soap. It goes away. I iron it and it comes right back (purple) HELP!!!!!!