Smeg dishwasher will not finish wash & pulses & blee

[d.o.n.]

Hi all.

Have an intergrated dishwasher model di612c and when it gets near the end of its wash cycle it will pulse as if pump is pulsing and beeps at the same time & will continue to do this for evermore as if its got a fault so will not finish its full cycle.
If I press the float valve underneath it will empty but this seems to just start the cycle again.

Any suggestions much appreciated