biomes o plenty activation

hi everyone!

first time doing this so im sorry if im doing something wrong.

i created a minecraft server here on aternos using forge to make a modded world with my friend and i wanted to add the biomes o plenty mod on it.

i already did it a few times on other servers and i know that you have tu change the world generation to ''biomesoplenty''/''BIOMESOP'' depending on which version you are using and it always worked,, but this time it just generates a vanilla world and i dont know what to do anymore.

please help

those are all the im using, maybe some of theme are not compatible with eachother but i dont know

It worked!

thank you so much, just one other question...is it going to effect my world generation in any way or is it going to work just as it should be?

and why didnt it work the first time doing it normally?