I just solved it, thanks for your reply. I have a mac (that is using the main .obsidian settings), and a iPhone and iPad using a second set of settings (called .obsidianios).
In the end what I did was create a new settings folder on the iphone, rather than using the folder that was already in the directory. I then copied over contents from my legacy (.obsidianios) folder into this new settings folder created by the iphone. The problem was that the legacy folder was just not being recognised by the iphone or ipad.