DW80R2031US/AA keeps dirty water at bottom

[Aqeel]

Model Number

DW80R2031US/AA

Brand

Samsung

Age

1-5 years

My 16 months old Samsung dishwasher model# DW80R2031US/AA keeps dirty water at bottom of dishwasher as if cycle is not finished.
Line, filter, pump everything is clean and good.
It started happening when dishwasher was just 7 months old, Samsung tech came and could not find any issue.
Earlier issues used to be once a 2-3 weeks, but now happens eveeytime.
We have to run wash cycle twice for it to clean.
Please help.

 

[Jake]

---->Make sure your dishwasher drain hose has a high loop in it before it connects to the garbage disposal or sink plumbing.

You can see how it has to loop in Fig 1, Fig 1a, Fig 2 here:

 

[Aqeel]

Hello.
I tried many options like putting drain pipe higher but that did not help.
Any given point of time, I've to run it twice to get dirty water out. If I'm out or if I forget, all dishes become stinky due to dirty water.
Could it be drain pump which is bad? During warranty samsung sent technician who could not diagnose it and reported ticket as closed. This issue was not that often earlier but now almost every run has this issue?
Please help.

Thanks and Regards
Aqeel..