Sometimes the garbage bots cannot get past the collumns (or however you type it), resulting in garbage being stuck near the elevator or on it, thus meaning the elevator cannot go down and you cannot techincally finish the round.
Garbage shouldn't be preventing the elevator from functioning. Were the near-by arrows lighting up green at the time?
Yes they were. Though sometimes you can go out with garbage in the elevator, but sometimes you cant.
I will certainly keep an eye out for this behavior during testing. Thanks for the report!