Did you try Junior's method? (https://www.playmofriends.com/forum/index.php?topic=4107.0)
That was my first go - though no neckpieces, or some new sculpts.. and sometimes it just doesn't work, no idea why.
These days I usually use the Neocon for kids with neckpieces.. yankers otherwise (because I find it hard to get a hold of them with the popper
)
I really haven't had much luck when I've tried that method before, but thank you Tahra & Graham for reminding me to try.. It worked & now she's looking all new & spiffy!
Weirdly I don't have many girls klickys with the standard head with brown hair like 30 11 2080 girl - the few i DO have mostly have either the classic body (& I have a soft spot for them & would prefer to leave them as is) or have neckpieces, aprons, etc, so I didn't think I'd have one spare to use, but I had the Pony Rider girl
K3119 & even though she had a collar, her head popped really easily. I guess the horsey girl gets into scrapes on a regular basis

).
I'm amazed it worked! (& reminder to self to get one of the Neocon thingys)