Hi Horia,
Thanks for the reply, much appreciated. To achieves the above-mentioned requirement I logged into the BC instance with the Admin account and followed the below-mentioned steps.
>> Click on the search button type 'Users' and click on the related link. On the users page selects the user who is unable to see another company.
>> Under the User Permissions Sets, in the Company field select the company you want the user to work with or Keep that field blank, if the company field is blank that means the mentioned permissions set is applicable for the user for all the existing companies.
