Hi @imkrishh,

thanks for the PR.
For future reference, here's also the ITU numbering plan, which is always a more accurate reference than a Wikipedia entry:
https://www.itu.int/dms_pub/itu-t/oth/02/02/T02020000E80006PDFE.pdf

It looks like currently only the following ranges are assigned and valid, which your PR is implementing, so thanks!
75, 76, 77
95, 96, 97

Also another reference for the future:
Real world random examples from Google Maps for those of these numbers
https://goo.gl/maps/4sNtcZAWjzkZKnin7
+260 97 xxxxxxx

https://goo.gl/maps/YbE5RygVAwBarQhj7
+260 76 xxxxxxx

Justone thing, that I think still needs to be done ideally:
Could you kindly also add an additional test for one of these new numbers into the tests as well?

Thanks!

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for future reference:
there is another (unrelated to this PR) issue with the en-ZM RegExp, but that is rather part of the discussion in #2124, so that shouldn't stop this PR from being merged after the updated tests are provided