Tree Huggers

As the Unfallen, extend Vines to 5 systems of an empire with whom you have signed a Peace agreement

So im not sure if this achievement is bugged or if ive just been doing this wrong.

So what i did was sign a peace treaty with the riftborn, then i sent my five fleets of vineships to entangle the five systems the riftborn had I was playing on fast and had built 5 fleets of ten vineships, so that the roots would extend in one turn, however the next turn rolled around and i didn't get the achievement so i said ill wait a couple more turns, maybe it hasen't detected that ive done it yet, however 10 turns later i still didn't get it so did i do something wrong? cause i might just be dumb.

Also: it has to be a peace agreement right? so not forced peace and not an alliance?

         it is only one empire right not five, cause i was thinking maybe it's supposed to be five different empires

so just to summerize:
built 5 vineship fleets

signed a peace treaty (not alliance, not forced peace)

entangled 5 systems

didn't get achievement

*Update*

got the achievement

what i did instead:

Built a ton of vine ships

spread vines to every cornor of the map

made peace with all ai players (not forced peace not alliance, also had about 7 ai sandbox difficulty)

so this forced them to have to settle where my vines were, so i guess that counts.