Hey Jatila,
Events Calendar Pro is the name of the plugin itself—there is no “Pro” service, per se.
You bought a Business License of the Events Calendar Pro product. This means you can use that product on three separate websites and get support for all three sites.
That license expired yesterday, however.
You have posted another thread about that expired license over here: https://theeventscalendar.com/support/forums/topic/already-payed-for-pro/
I will close this thread and keep the conversation in the thread linked above to keep this organized.
Thank you,
George