This is actually different but in an unexpected way.
The result that i get is: -rw-rw---- 1 uhttpd dnsmasq 1480 Apr 3 09:43 /etc/config/dhcp
so the user uhttpd has permision to read and write and all the users in group dnsmasq also have permission to read and write.
If user uhttpd is not in the user group dnsmasq then the user uhttpd cannot read or write to file.
The user uhttpd is the RUTS webserver and as i understand things the WEBUI cannot write to the file. It doesn’t have permission to do so from the system.
So i’m thinking that the user (NOT THE GROUP) needs changing to uhttpd.
This is what i’d do but i’d also want to have clarification that this a solution from a teltonika engineer before doing so, just in case.
chown uhttpd /etc/config/dhcp