Engine warning came on Dashboard of Skoda Rapid diesel

My car is Skoda Rapid Tdi 2012 model.Till date it has run 74000 km. Last service done was 19th Jan 2019. Since the car has run only 7500 km after the last service i have not observed 365 time period. Now the car has run 14 months without service(two months overdue). The engine oil level is maintained by adding half lit same synthetic oil from Skoda. I had run the car about 500 km on 18th Mar 2020. On 19th morning when started the car the engine warning appeared on the dashboard. Thinking that it is due to service overdue, I myself reset to 15000 km and 372 days. Then the warning disappeared. I started the car various occasions after the incident and warning never came again. When I enquired the Skoda service station, they told the engine warning has no connection with service overdue. Now i feel unsafe to drive the car. I now tightened the fuel lid also. In one of the posting of stackoverflow it was reported that if the problem is major the engine warning will not disappear its own. Now please advice.