Messenger and emoji glitches

Hi. When in Facebook Messenger, if I try to scroll up to reread my message (to make any necessary corrections), the text bar “closes” where I can see one line of text and a white, partial screen comes onto the Messenger screen from the left. I often must delete my message and start again without being able to go back and edit.

With the emojis, I’ll open the emoji screen, and when I touch an emoji on the screen, hNO KEYBOARD, the emojis collapse off the screen. Both of these issues are extremely frustrating. Please provide instructions on how to remedy these issues. Thank you.