The Control Lock is a safety feature that allows the consumer to lock the control panel to prevent small children from manipulating the controls. It can inadvertently be set following a power outage, or by leaning against the control panel.
If this is a Maytag Epic, Whirlpool Duet, or Kenmore Elite, the following link explains how to lock/unlock this feature:http://www.fixya.com/support/r3608801-control_panel_lock
These instructions are also printed on the front panel of the appliance and in the owner's manual. If this does not correct your problem, then you may have a more serious problem than a simple operator control issue. If you need further assistance, please let me know. I hope this corrects the problem for you.
NOTE: If you cannot locate your owner's manual, you can download or print a FREE copy at managemylife.com. Just type in your model number under the "Manuals" link and you will find your manual listed in a .pdf (Adobe) format.