Maintenance and cleaning is not covered in the core step-by-step course itself, however I’ll be adding more videos and sections to the site in the very near future, one on maintenance and gear! In the meantime, here’s my answer to a similar question. https://mitchgrainger.com/MembersForums/topic/getting-started/#post-2767
And, by all means unscrew your harmonica cover plates and take a look inside. You can use rubbing alcohol to give the reed plates a wipe, being extra careful not to push the reeds them self to hard..
P.s. Glad you like the new look, I’m putting all my spare time into improving the functionality right now and then i’ll have the scope to add much more content, which is the end goal. 🙂