Сhunks error

I have been building my card for a long time and after updating to version 1.14 there were errors.
Errors in the chunks - some of the chunks on the map became light, every day there are sources of light everywhere (on skin shots) - this is very annoying and I don't know how to remove it ?! And finally, after the update, the chunks began to load and reload more slowly. In the previous version it was not!