One of my fish has gone missing in my fish tank. ?

This evening I went to look at my fish and noticed  I couldn’t see one. My tank is only 30L and I did have 3 tiger barbs and 3 Cory catfish. However I was looking and could only see 2 of my tiger barbs this evening, after a while of looking I decided to open the filter and look through my entire fish tank (basically moved everything) and it literally nowhere to be seen. I am so confused as I know that it was there this afternoon as I was literally looking at it. It’s not like it could have jumped out my tank either as from the time I last saw it (this afternoon) to now I haven’t opened my tank and it’s been sealed shut. I feel like I’m going mad lol, is it possible that it could have died and been eaten by my other fish in such a short space of time?