bf texts me on all apps but has ignored me on discord

me and my bf are long distance and have been together for 2 years. i sent him a text abt 4 days ago on discord asking him a serious question abt a conversation we had previously and while i was talking w another friend i saw he was active but didn't answer. i thought maybe he needed space and time to answer so i left it at that. and then the next day i asked him something else on a different topic (again on discord) and still no answer up to today. BUT he texts me frequently on insta and snap so i'm confused as to why he would ignore my messages on discord. idrk what to do or tell him bc i'm not a confrontational person :/