Gears5 ending weird

first love the game,

but didn’t like ending that much was a bit boring, I didn’t get my achievement for completion.but did any one noticed at end it kinds of bugs out like it wants to load something else??? after killing the boss which was easy it ended rolled the cutscene then the credits but then it went back into the game and let me move the character for maybe 2 seconds then glitched out and went to main menu.

any one any idea?

cheers