Yes it was removed because it contained no value and pdns cleaned them up because updates from your zone would not work otherwhise.
Yes, you have to recreate the record.
If the record is empty - the DNS Master is unable to send the new updated records to the slaves and that renders your zone unusable when you are updating other records because they are not propagated.
What mobile client do you use?
A instance dedicated - but not limited - to people with an interest in the GNU+Linux ecosystem and/or general tech. Sysadmins to enthusiasts, creators to movielovers - welcome