I actually thought this was a McAfee message, nice job 
3 Likes
As stated earlier, you should have actions against false mod call requests (along with a message warning within the mod call UI).
Within your mod call UI, it says to “Provide Proof”… There is no way of determining if their proof is actually 100% valid considering that the user could say anything (also considering that you can’t send screenshots of the game via this system directly)
You could with Gyazo, Lightshot, etc. And I do have certain precautions against false calls one being a blacklist from the system. 
I feel that the Text being Scaled is too much, I think you should move the margins of the Mod Call title up a bit using UIPadding and then and then use UITextSizeConstraint to make it so the text isn’t so big. The confirm button and cancel button are too close together. Colors are also a bit harsh. Other than that I think it is good!
I really like the minimalist design. It looks like you’re going for a Material UI look.
If that’s the case, might I suggest adding some minimal shadowing underneath your header and button. It adds just a little bit of depth.
You could also consider switching from straight white to a white with a very slight green hue. This is common practice, and if you want a colour palette to reference then I would suggest this. (I reference this whenever I’m designing UI)
I look forward to seeing the finished product!