Full And Final Settlement With My Previous Employer

I worked in XYZ company from November 2013 to April 2018 and moved to the UK on VISA ICT (Internal company transfer visa). 1. While the working CEO promised me that, if I work till June 30th, he will give 5000 pounds on arrival to India, and I had continued there for some time and resigned on Aug,3rd. After I reach India, They are not replying to my emails. 2. Will I eligible for gratuity. 3. I was having ESOP shares, Recently I heard that another company acquired XYZ company in April 2019. What happened to my shares?