Preview feature not working

Expected behavior

When making a post i expect to be able preview what am writing to make sure my markdown is correct and the rest

Actual behavior

I tried to use the preview feature but its not working

How to reproduce

download the app
login with steemit details
click the plus sign to make a post
click the eye logo above to make post
hold down for preview to pop up
click it to preview

• Browser: infinix note 4b pro
• Operating system:nougat

a video to reproduce