してたのに

even though I was doing

→ 為る
phrase Common #7,218
even though I was doing A casual contraction of していたのに. The subject and the action being done depend on context.
JA: 勉強してたのに、寝てしまった。
EN: Even though I was studying, I fell asleep.

いいこでおねんねしてたのにね

You were sleeping so peacefully, too.

— 千と千尋の神隠し (2001)

せっかくリードしてたのに

Even though we had the lead...

— ライフ・イズ・ビューティフル (1997)

学生デモばかりしてたのにいつ勉強したんだ?

You were always out protesting with the students, so when did you study?

— グエムル -漢江の怪物- (2006)

ずっとガマンしてたのに仕事があるの

Even though I’ve been putting up with it this whole time, I have work to do.

— TAXi (1998)