perhaps you have a partial blockage. I'd suggest you remove the pipe TO the pump and see if water flows through this OK(a kettle or saucepan to dump it in and a washing-up bowl under the pipe are a good idea.
If OK, you could repeat with the hose reconnected and observe the output from the waste-pipe.
If the pump is new...that eliminates fluff.elastic hair-scrunchies etc. caught round the impellor (pump still spins but produces much reduced flow.)
that leaves the outlet -pipe.......remember that a trapped coin can act as a flap-valve and flip-over to block the flow.
AFAIK, many machines will allow a preset time to pump-out, then carry on the cycle. so if the pump can't clear the last lot of water....the next stage still carries on.(or you get an error code
old enough for wisdom, young enough to be compos mentis.