When you disassemble a tent or sleeping bag sometimes the marker stays on the map and still functions as a respawn position, even though there is nothing there any more.
The marker should be deleted from the map along with the tent or sleeping bag & respawn location.
Due to this bug the map becomes cluttered with lots of available respawn positions when you die.
(This bug was discovered on a persistent server and was noticed by players when when logging off and on)