Sounds like you have a modified LuCI source repo with some additions from you (or from somebody else). Likely those modifications have been targeting an older/newer version of LuCI, and as LuCI has changed since the authoring of those changes, you need to modify your own code bits accordingly. As nobody else knows what you have done, it is up to you to solve the conflict.
(your previous posts have already indicated that you are messing up with non-standard stuff like Is LuCI 19.07 stable version and can it be used along with OpenWRT 18.06.02 stable version? - #3 by ravink , so if you ask for help, please clearly clarify what are non-standard parts...)