Missed that ?
Drawn a blank with information about this specific model, but Neff's own site has this advice for door closing issues:
Problem category: Malfunction
Issue: Door function defective
Door can't be open or it is difficult to open
Cause
Childproof lock is activated
Resolution
Press lever above the door (childproof lock) to the right and open door.
Door does not close properly
Cause
Door lock is snapped over
Resolution
Close door with increased force.
Not sure that it's particularly helpful, but does suggest that child lock issue would likely prevent door from opening, rather than closing.