sprites are invisible when i launch the game on iphone

I have sprites that are visible in the editor but when I launch the game on my iphone those sprites disappear. I’m using textures 1024*1024. any ideas?

I solved my problem in a weird way, first when I import the textures I have to open the texture and change its format to (user interface). then, for some reason I don’t know why, I have to close unreal and re-open it again. after that when I launch the game by the launcher in my iphone, everything works perfectly.
I think the problem that unreal does not update the textures when I change their formats that’s why I have to close it and open it again.

Just faced similar issues
My case was as usual

Sprite Translucent Sort Priority

My sprites were covered with another one, with bigger sort priority. It is behaving differently in editor and on the phone.