Flashing lights 1 and 3 is pressure switch error.
You will have to unplug the appliance and pull it out, then tip it backwards by around 45 degrees so excess water drains off completely.
After you have done this, check the drain hose where it connects to house drain and make sure it is not clogged.
Then please clean the mesh filter from inside and make sure it is not blocked.
Now, reconnect everything and plug it back; select any program.
It should work however, if the problem occurs again you will have to unplug it again and then remove the right side panel.
Then pull it out and lay it on its back.
Towards the bottom right side, you will see pressure switch with thin hose attached to it.
Remove this hose and blow through it, make sure it is not clogged.
Then reconnect everything and plug it back, it should work.
Please let me know if you need me to clarify anything or if you have any additional questions-I am happy to help!
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