HAS exam is for various posts under HPPCS.
So , following are the eligibility criteria:-
1. Can you do it must be a citizen of India
2. Candidate's age should be from 21 years to 35 years
3. Candidates who are familiar with Himachal Pradesh dialect , customs , environment and traditions will be preferred over those who don't.
So even if you are from Punjab and not from Himachal Pradesh will not matter much.
But it will be like icing on cake if you would know about Himachal Pradesh's customs , traditions and dialects.
Best Of Luck!!!!