Updating a modded world from 1.12 to 1.15

So basically, I want to know if it's possible to update a modded world from 1.12 to 1.15. I worked on a mod in an older version of Mcreator and used it to build my map, and I already updated the mod without problem and worked on it fine, but when I open the map with the updated version of the mod in 1.15, it erased all mod blocks and erased the contents of modded dimensions. Is there a way to smoothly update a modded world and keep it's integrity intact?