Core Form?

Hello Blender Peeps!

The other day I was doing an FB Reach core routine and my neck kept burning a lot (my core was working too) but mainly my neck. I know that, that is most likely because instead of using my core to lift myself up I use my neck instead. I don't mean to do it so it isn't on purpose. I always feel like I'm lifting with my core....until my neck starts to hurt so I always have to stop and readjust which makes me miss a lot of the time to do certain exercises. I feel like because my core isn't the strongest and because I haven't worked out for a while my neck could be compensating for it so maybe I should wait until it gets stronger or stick with standing core routines? Is that a bad idea? What can I do to fix this and correct my form? Any tips appreciated. (Apologies for not responding to anyone who comments. I tend to forget I post things. 😅 I do read them though.)