Hard to say whats wrong without seeing project. There are a lot of ways to sidechain -Have to say that i am a fan of the FLs simple curve version. Dislike 'Classic' sidechain with sliding knob -Its an overhead and its not necessary, but does work.
Give this a look, and see if that works for you:
https://docs.lmms.io/user-manual/7-reso ... ve-effects
Besides that, since you are new in Forum
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