Flip off the two breakers closest to the melted area.
Turn the power back on (except do not turn the previously mentioned breakers on).
See if other circuits are working correctly and you do not hear sizzling.
Optional: Take a wax crayon and press it on the melted area. If the crayon melts then you have further problems and you need to turn off the main breaker again.
You can unsnap a breaker (notably the two closest to the burned area) to check the bus bar underneath. If you find the bus fins under the breaker burned or discolored or deformed then do not put the breaker back. Instead, unscrew the breaker from its wires, label the wires, and tape the wire ends securely.
Turn the power back on (except do not turn the previously mentioned breakers on).
See if other circuits are working correctly and you do not hear sizzling.
Optional: Take a wax crayon and press it on the melted area. If the crayon melts then you have further problems and you need to turn off the main breaker again.
You can unsnap a breaker (notably the two closest to the burned area) to check the bus bar underneath. If you find the bus fins under the breaker burned or discolored or deformed then do not put the breaker back. Instead, unscrew the breaker from its wires, label the wires, and tape the wire ends securely.