Oman Valid phone number shows a error.

Oman latest phone number shows a error.
Update the phone number validation for Oman.
Sample Number :
+968 77****** - > starts with 77 , 8 didgit number.

Start by locating the Oman phone-number validation entry point and any existing country-number tests. Check the handling of numbers beginning with 77 and containing eight digits, then verify that the supplied +968 77****** example is accepted without breaking other Oman formats.

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