It was not hacked. There was small problem due to poor web security. Now, they have sorted that out. There is no problem. Thought they don't provide good online banking service.If  you want online banking from Nepal, Standard Chartered Bank is the best one. But, If you are in UK then Kumari bank could also be best for you coz they are going to open their branch office in London...

BTW, there is nothing to hack in Himalayan Bank web site:)