When I try to delete the form created in xyz page . I get ResourcrLockedError. Kindly help me delete this page.
Try going to 'edit' for that document, and then click on the 'Cancel' button.
It should clear up the lock.
Cancel really reset the lock? In that case you could capture the lock from a concurrent editor and undermine the purpose of the webdav lock/edit lock as a whole.
Got to the ZMI, /Control_Panel/DavLocks an insert in the Formfield the Path of the Parentobject of your Page wich you want to delete. Unlock the Object and now you can delete the Page in Plone.
IIRC a concurrent editor would have first to go in edit mode (unless the concurrent editor has admin rights, bypassing the protection) so only the same user or an admin can unlock by editing and cancel. It's rather well thought out in fact.
this worked for me, trying to delete a page in Plone 5.1.6