The submit button do not shown

Why the submit button in the bottom of the survey do not shown?
and when we ask the respondent to refresh the page, all of the answers are lost.
please, i need a quick response.

Can you change the screen colour theme to white, instead of black?
You are using Webform/Enketo, with browser from Android smartphone?

It seems to work fine in Android Collect. Local project setting in Collect: User interfacce - Theme. (Or on device itself).

i got the screenshot from the respondent. i guess it’s because of the browser. i’ve contact her to open kobotoolbox using chrome instead of another browser.

thanks a lot for your response.