Can i deactivate my license code for a wordpress theme on a website that is already deleted (domain expired) and reactivate it on my new website with a new domain ?
Your best option is to contact the author of the theme, and chat to them to find out how best to proceed.
Bear in mind that the author may reject your offer as 1 license = 1 domain.
When you change the domain name ( except typo ), you’re obligated to purchase a new license according to the Envato policy.