Front load washer fills with door open

We have a Duet washer Model # GHW9150PW0. We returned home yesterday after 13 days to find water all over laundry room floor. Washer door had been left open as we always do. Water filled tub then on to floor. Is this normal? Any idea on what has failed? All hoses are tight and not leaking. We have done 7 loads of wash since with no problems. Insurance Co. is demanding a repair invoice to show it’s been fixed. Any help would be great. Thanks

Here are your parts
http://www.appliancepartspros.com/partsearch/modelsearch.aspx?model=GHW9150PW0

Sounds like the inlet valve may be leaking.
To confirm this unplug the unit and and see if you can her water entering the tub.
If no sound leave it for a few days to see if water is filling the tub, just check it on a regular basis.

If it is filling then I would replace the valve.

Here is a manual which should help with the repair.
Although not an exact match it should be close.
http://appliancedigest.com/index.php?/files/file/324-l-68-whirlpool-duet-front-loading-washers-service-manual/
You have to join the site to download the manual but it is free and this is a very good site for manuals and other info for the appliance repair DIYer.

If it does not fill then my guess would be that the valve leaked just that one time or the control board went weird and turned the valve on.