This rare kanji has no clear standalone meaning. Treat its meaning as uncertain.
The exact historical development is uncertain. The modern form combines the grass radical 艹 with 煩, but the original semantic and phonetic roles of these components are unclear.
The grass radical 艹 sits above 煩, which suggests worry or trouble. Picture a patch of troublesome weeds that are hard to identify—just like the uncertain meaning of this kanji.
For ハン, imagine a hand pulling up the troublesome weeds: hand -> ハン, and your hand clears the uncertain grass.