The major product formed in the following reaction is

Concept:

• Methyl amine (MeNH₂) can act as a base as well as the nucleophile.  
• if substrate has acidic proton, it will preferably act as the base and abstracts the most acidic proton.
• the H is considered acidic if the negative charge formed after  its abstraction can be stabilized by conjugation or presence of some electronegative atom.

Explanation:

• In the first step, Methyl amine will abstract the most acidic proton attached to N in 5-membered ring.

          The generated negative charge is resonance stablized.

• In the next step, negative charge will move to C and will substitute Br^- to form 3 membered ring (SN²).

• Next step will follow up with  nucleophillic attack of another methylamine molecule at electrophillic carbon centre of Carbonyl bond.

• Finally, the back conjugation of negative change on O, will facilitate the breaking of  3-membered ring (which is unstable) in such a way that the aromaticity of 5-membered ring is regained.

Conclusion:

The final product of the reaction is :