に来たのに

even though I came to…

→ に
phrase Rare #33,937
even though I came to… に marks the purpose of coming, and のに expresses contrast or an unexpected outcome.
JA: 手伝いに来たのに、何もすることがない。
EN: Even though I came to help, there’s nothing to do.

仕事に来たのに-散歩する歩いて見物してばあさんに見せたい

I came here for work, but I want to take a walk, see the sights on foot, and show them to Grandma.

— ベルリン・天使の詩 (1987)

せっかく東京に来たのにずっと雨だね

It's a shame it's been raining the whole time, even though we came all the way to Tokyo.

— 天気の子 (2019)

だから桟橋に来たのに何が不満なんだ?

So what are you complaining about? We came to the pier, didn’t we?

— フォーリング・ダウン (1993)

助けに来たのに!

I came to help, for crying out loud!

— インディ・ジョーンズ/最後の聖戦 (1989)

せっかく東京に来たのに

Even though I came all the way to Tokyo...

— 天気の子 (2019)