RESIGNATION VALID OR INVALID?

I passed my resignation year 2015, my employer ask me if I can just stay for a while until they found someone to replace my post, assuming he means the 30 day period with a condition that I will only be reporting to work when needed but my license will stay for use by the company, I agreed. 30 days passed, then months then years, I never heard anything from them and Im just enjoying the type of work they have given me until sept. 2018, where they call for a meeting and tell me they already found a replacement and they are releasing me. I dont know my status, I worked for almost 8 years in this company as a regular staff, they took my letter but didnt send any acceptance, everything was verbal. Am I entitled to a separation fee? Anyone, please help. Thank you.