when ever i created a map the pointer didn't appear,until i placed it in item frame.Then,after the pointer appear in the item frame,i take the map and travel around ,but the pointer didn't move at all.
step to reproduce:created a map then put it in item frame,take it back,and travel around....look at the green pointer shown in your map...
works as intended. when placed on an item frame, it shows current location in the map.
if you want to be marked in the map, merge it with a compass on an anvil.