Hi welcome to health care magic forum,
Some variety of mango may cause allergic reaction
Allergic reaction may manifest as irritation of throat , with red and congestion of throat.
It may leads to itchy lips with edema(swollen).
Sometimes generalized body itching and redness
But you said it happened only twice , so nothing to worry.
In my opinion you can take an antihistamine medication .
Take plenty of water and avoid spicy food .
If no relief than you can see an ENT specialist
for clinical evaluation.