What does this “not secure” message mean?

Feedback Usage & Design
1

I setup my router to use 1.1.1.1, but I just noticed that if I disable the WARP apps on my iPhone or iPad, it says “ Your network is using 1.1.1.1 but is not secure”. I thought using 1.1.1.1 made it secure. What am I missing? Thanks for the help.

3

I should note, it says this message inside the app where it usually says “your connection is private” once warp is activated.