A feedback or feedback? The word English never counts.

You said it in the meeting and everybody understood you. „We had a nice feedback from the client.„

Nobody corrected you, because nobody needed to. The meaning arrived intact. The only snag is the „a„.

A few English words are never counted. Feedback, advice, information, news. No „a“ in front, no „s“ on the end, however much of it there is. You can’t have an advice either, though plenty of people try.

That’s the whole of it. One small word and nothing else about your sentence changes.

(I hear this most weeks, and I’ve never once misunderstood anyone who said it.)

Quick win: „We got good feedback.“ No „a„, no „s„. Same meaning, one word lighter.