When I worked on drawings with a many datum tags. Trying to re-assign references or moving them would cause a fatal error crash very often. I have given up on using actual datum tags and resorted to an intelligent datum tag symbol for the drawings.
In the last post in the linked post below, there is a symbol attached that you are free to use if you so choose.
Datum Tag problem
What version of Creo are you using, Nandkumar?
And welcome to the forum!