Really ah. For me I did that + allow whatsapp to run in background also cannot. The msg will delay a few hrs. Until I turned off MIUI optimization then nv missed one since.Go to the security apps > Permissions > autostart and auto start for whatsapp...No more delayed whatsapp notification...
This prob quite cui.......a lot of ppl complaining on MIUI forum. Out of the box shld not hv this kinda issue at all. Lol.
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