The bees that spawn from the multiplier aren't returning to their hives at night as each hive is capped at 3 in vanilla. Might be nice to have a config for hive size.

Mod: Realistic Bees

Thanks for the suggestion! I totally agree. I've just released Realistic Bees version 2.5 which adds the feature. By default now 20 bees can enter a hive, but this can be changed in the config.

https://www.curseforge.com/minecraft/mc-mods/realistic-bees/files