Can't remove child lock programme accidently set on my Siemans S14-79 washing machine so can't remove the washing

If the machine has taken in water, and not drained it out. it will prevent the door from opening.
Have you tried draining the machine, and then trying to open the door?? The easiest way it to either set the machine on a slow spin cycle, and allow it to finish that, or if your particular machine has a "drain cycle" ( this feature is not on all models) set the machine to drain, and when it has finished, try opening the door. I hope this helps?

Child Lock
?When activated all the buttons will be disabled and a child will not be
able to alter any wash programme or option settings. Once selected
this feature remains activated, even when the machine is 'off'.
To use this feature press the 'Child Lock' button and hold down for 2
seconds.The child safe icon will begin to flash.When the icon stops flashing
the feature is activated.If any of the control buttons are pressed, the child
safe icon will flash and the machine will bleep 3 times: no alterations to the
control settings will be allowed.If power is interrupted, at any time,pressing
any button will reactivate the child lock feature.
To deactivate this feature hold the 'Child Lock' button down for 4
seconds.You will then hear a bleep and the child safe icon will go out

The display will have a icon for a lock. It may be for one or two buttons to be held for 5-8 seconds to unlock. It's the same thing as locking it.

Hold the child lock button down for 6 seconds until it bleeps

To dectivate child lock press the key with the clock symbol for 5 seconds. The child lock will deactivate.
If it still does not then you may have shifted the programme dial. Rotate the dial through each programme and try deactivating child lock in each programme setting. The child lock will deactivate only in the original setting that it was activated.

See your manual to reset the child lock. If you see the child lock button, press and hold it for 3-5 seconds and it should beep to reset.

If that doesn't work then unplug the unit for 30 seconds and try it again.

Your problem is either one of the 2 cases below.

1. Door Locked Indicator...'Keyhole' symbol
The 'Keyhole' symbol will illuminate 2 seconds after you have
pressed the 'START/CANCEL' button and will remain lit
throughout the wash programme.
The 'Keyhole' symbol will be flashing at the end of the
programme to indicate that the door is still locked. When the
symbol goes off you will hear a bleep and the door can then
be opened.

2. If the machine has been child locked, deactivate this feature by pressing and holding in the 'child lock' button for 2 seconds.You will hear a beep and the child lock symbol will go out,allowing you to use the machine normally.

The child lock comes on when you press the child lock key for two second. To remove the child lock, press the same key for 4 seconds, this worked for me when I recently faced the issue!

When activated all the buttons will be disabled and a child will not be able to alter any wash programme or option settings. Once selected this feature remains activated, even when the machine is ‘off’.

To use this feature press the ‘Child Lock’ button and hold down for 2 seconds. The child safe icon will begin to flash. When the icon stops flashing the feature is activated. If any of the control buttons are pressed, the child safe icon will flash and the machine will bleep 3 times: no alterations to the control settings will be allowed. If power is interrupted, at any time, pressing any button will reactivate the child lock feature.

To deactivate this feature hold the ‘Child Lock’ button down for 4 seconds. You will then hear a bleep and the child safe icon will go out.