Simple question. Do you act over the 1NT opening?
I'll go ahead and give the full hand below, because what happened at our table was somewhat interesting.
Scoring: IMP
Bidding at our table went:
(1NT)-P-(P)-2♦
(2NT)-AP
Bidding at our table went:
(1NT)-P-(P)-2♦
(2NT)-AP
In our methods, I actually do have a bid for my hand. We play Astro, and at these colors I probably should have bid 2♣ (my hand is weak, but the shape is to die for), showing at least 5-4 Hearts and a lower suit (the ♥s can be the 4 card suit). But I blanked on whether the correct bid was 2♣ or 2♦, confusing it with a much different, unrelated sequence. So I passed.
That allowed my partner to use Astro. Initially he misclicked and bid 2♣, but asked for an immediate undo and bid the correct 2♦. After having a few more seconds to think about it, I knew the correct meaning of the bids, and knew we had a terrible misfit going, so my pass was easy.
2NT went down 1. It wasn't a top, but still a tidy +1.43 IMPs for us. If I had bid correctly we likely end in 2H, which goes down 2 if I look at things right.
Not as interesting as declaring 3♦xx holding 1 HCP, but that is a different story.

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West opens 1NT. Your bid.