Here is a link to the USER'S MANUAL for that model of washer:http://products.geappliances.com/MarketingObjectRetrieval/Dispatcher?RequestType=PDF&Name=49-90392-2.pdf
Just click on the underlined text above to view an electronic copy of the manual.
On page 8 of that manual you will see instructions related to the LOCK feature on your washer.
It says that to LOCK or UNLOCK the washer, just hold down the DELAY START button for 3 seconds. The lock icon on the display should then disappear.
If that does not work for your model, then try holding down the SIGNAL button for 3 seconds.
One of these two procedures should solve your problem.Hope that helps.
Take care and thank you for using FIXYA.