My streak says at risk but I trained yesterday

Resting is part of the streak. You can take 2 days in a row without training and keep it, so skipping today is usually still two nights away from any deadline.

Kovo only warns you on the night your streak would actually end. An ordinary rest day does not set the warning off.

So a rest day on its own is safe. Your streak ends on the third day without training, and not before.

Learn more: How does my streak work?