I am evaluating HP OO and it's trial license is going to expire soon.
Is there a way to extend HP OO trial license. If yes, how and whom to contact.
The trial period for HPE OO cannot be extended. It is set for 90 days and once it expires the only way to continue using it is to buy an enterprise license.
If you need to test HPE OO for longer periods why not give the Comunity Edittion. It has all the same functionality as the standard edition, however you are limitted to 500 flow executions per month on Central. This limitation does not apply to studio executions or remote debug flow executions.
Hope this helps,