Bf ignoring me

I'm in a long distance relationship w my bf for 2 years and a half now. We chat everyday for hours sometimes. I work from 7am to 3 and he from 2pm to 11. We used to talk even when we're at work. The last two weeks he started to not text me back until like 10pm or at midnight (he knows that I sleep around 9). Like the whole day when I text him he dont respond at all until its my sleep time. And when I told him about it he just said "sorry I'm busy at work". He could reply when he's going to work (he use Uber) or at his break. Even at his work he use his phone and go on social media but too busy to text me!!! Like idk what to do anymore it just makes me mad at him for neglecting my like that. We were good two weeks ago idk what changed!