1) Confirm your submit button settings are correct. You can check these by logging in to emailmeform.com > mousing over the form you want to check the Submit button settings for and clicking "Edit" > clicking the "Form Settings" tab > scrolling down to the submit button settings:
2) If you have a Theme applied to your form, verify that your Button Type selection is correct. When referencing or uploading an image, please ensure that the URL is valid. Alternatively, you can also set the theme to follow your form settings.
3) It is also a possibility that your iframe width or height is off. To adjust the width or the height of your iframe, you must log in to emailmeform.com > mouse over your form > click the "Code" icon > copy the code for iframe (if you are using this version) > modify the code with the correct sizes (varies from site to site) > upload the code to your site. This will give your iframe enough room to display your submit button.
It is also possible your form is no longer accepting submissions due to it reaching the maximum submissions, to reset these, read this article on resetting monthly submissions.