Freezing and units disappearing issues on going

Platform- Xbox One
Region- USA
Gamer tag- dxbox0
Issues- During skirmish, units transported by enemy AI (shipmaster) still disappear into a section of the map that renders them unsable, as if below ground. Also, the game still freezes and crashes every so often once exceeding the 100+ minute mark (in 3v3 skirmish). Been playing it off and on due to these frustrating problems, but see they still exist.