ながら（も）
nagara (mo)
although; despite; while (being)
[Although / Despite / While (being)]
Connection: Verb (ます stem) / い-Adj / な-Adj / Noun + ながら（も）
Usage: Expresses a contrast — although a certain state or fact exists, the result is contrary to what would be expected. Different from the simultaneous-action ながら (N4).
Key point: This is the concessive usage, not the simultaneous action usage.
Examples:
知っていながら、何も言わなかった。(Although I knew, I didn't say anything.)
残念ながら、お力になれません。(Unfortunately (while it is regrettable), I cannot help you.)
狭いながらも、居心地のいい部屋だ。(Although it's small, it's a comfortable room.)