So from the way you are saying it functions you need to make two changes.
1. You need to pattern match the extra stuff out of the variable that is created when looking at guild notes. For example, below is how I grab multiple inputs from the slash command. It puts the first word in "command", and then the rest into "rest". You can most likely use something similar when scanning guild notes. So if you have them put "weekday" or "weekend" as always the first word in their guild note, you can probably work from that.
Lua Code:
local command, rest = msg:match("^(%S*)%s*(.-)$");
2. After grabbing the first word from their note and storing it in its own variable, run a string.lower() on the variable and it will remove the capitals and make it work.