ho19sjr:

I am sorry to say that you are not likely to receive much helpful advice when you supply so little information about your mango tree --- not even your location. Do you live in the tropics where a mango tree might be reasonably expected to grow, or are you trying to grow a containerized seedling?
A few brown or curled leaves might be due to several factors, including soil chemistry, moisture and temperature.

Highly skilled container growers using named dwarf varieties have been reported able to fruit mango trees in northern climates, but these instances are uncommon and the mangoes thus produced cannot rival a good field-grown mango. Trees grown in containers from supermarket seeds are essentially pets, not fruit producers, and are touchy and difficult to grow because of the conditions required.

There are not many people here who would try to grow a container mango tree, so if that is what you are doing you might have better luck on the container forum.

Don Yellman, Great Falls, VA

in the ground in our area, that would usually be they didn't get enough water at some point. But as jelly said, could be a lot of things.