usually this error means that the chapters werent combined the right way. you should download the chapters again and merge chapter2 into chapter1, start the game and check that the game version in the lower right corner is 2.09, and then close the game and merge chapter3 (if you have it) into the folder with chapter1+2.
i hope it helps, but if you still have a problem with merging the chapters you should join the discord channel and ask for help there, it will be easier to communicate.