Lock iMessage from other users on iPad

Hi Hkatwells, thank you for posting in Apple Support Communities.

If I understand your post correctly, it seems you may be sharing your iPad with other users and possibly wanting to ensure each user only has access to their own messages.

If that is the situation then it is preferable that each user has their own AppleID (if they do not have one already). Please look at the link which recommends avoiding sharing an AppleID:

https://support.apple.com/en-us/HT204976

Having said that, even if each user has their own AppleID, to share the iPad, which I would not recommend, you would need to treat the iPad as if you were selling it or giving it away before each person can use it and also after they finished with the iPad. This will ensure there are no legacy issues with the iPad for the next User. The following link explains in more detail how to do this:

https://support.apple.com/en-au/HT201351

I apologise if I have misinterpreted your post and happy to provide further advice if needed.