how to increase the size inside the text box for mobile usage

I want pls.  to increase the size inside the text box for mobile usage, it is small when u check it by smartphone?

Thank you for contacting us.

I have checked your form, and the text boxes look normal on my mobile device.

If you would like to have multi-line text inputs, please consider using Text Areas. You can control their sizes by changing Columns and Rows parameters.

If you need any further assistance, please let us know.

Dear thanks, But the text box is flexible,  the size is not adjustable & can be changed by user in smartphones also it will make different shapes of  the fields within the form so they will not look equals , also the user will be able to

in my form I need to have the input font size bigger, so I can see them in smartphones pls.

As mentioned by my colleague you could try using a text area for the comments section and modify the rows and columns to make it look the way you want.

If you take a look at this cloned version of your form: http://form.jotformpro.com/form/50693681234963

This is how it looks when the form is viewed on a desktop.

And this is how it looks on a mobile device.

Please give it a try and let us know if it looks different on your side.
Thanks.