Can't move my units into city (even with movement points left)

Hazz-JB

Since I went from vanilla to buying all the DLC, there are some turns where I cannot move units into my cities after moving them across the map. They just walk right up until they're touching the city, then stand there. They have movement points left because I can still move them. They stay stood outside the city but are unable to go in. The city has plenty of space for units and is not under siege. I then have to end turn before I can move them into the city. This is really stupid and annoying when I need units in the city for repression or defending against an incoming army on THAT turn. Has anyone else experienced this?

Mechwarrior5#7885

In my experience, you need some MP left to get into city (approximately, as much as needs to pass by road from outside to some inner point). BUT IF there is already at least one unit in the city, you have to spend few more MP for «merging armies». The hint is to keep the city empty until the army enters.