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dheeraj115 wrote:

is there any chance that Apple include this 13inch model as well in Keyboard Service Program for MacBook, MacBook Air, and MacBook Pro, like they have included 12inch 2015 model

Yes,

See if you qualify: https://support.apple.com/keyboard-service-program-for-mac-notebooks

If you have a non-USB-C model, then there is no free keyboard repair program. You just have a bad keyboard which you will need to pay to repair unless of course the failure is due to dirt, crumbs, or liquid residue which can be cleaned from beneath the key. If the key cap or scissor mechanism is damaged, then you may be able to find a replacement scissor mechanism and key cap online, but you will need to be sure to get the correct type as Apple has more than one type of keyboard and the scissor mechanism & key caps are not interchangeable between the different versions of the keyboard.

If you have a USB-C model, then the repair may be covered for free under the free keyboard repair program mentioned by @leroydouglas.

Take it in for servicing.