Some compost applied as a topdress or instant topsoil, on top of the soil where a mango is planted--- if applied in moderation, such as one inch deep--- is usually great.
But when mangos are planted in a pot of compost, or in a pot of organic matter that turns to compost, it will consistently become a sick or dead mango. The same happens when a planting hole is stuffed with compost or with potting soil that later turns to compost. Those techniques are usually fine for veggies and bananas, but almost always terrible for mangos.