Seems like your issue is same as mine fixed on qk9services contact page by removing the site borders and paddings via CSS.
Solution: I’ve resolved similar problem by removing borders and padding from the page, you can do this by inspecting the code CTRL+SHIFT+I or view source (CTRL+U) then find the component causing padding and remove it via CSS. If you still can’t do this, let me know so I can help you via anydesk remote access. Good luck!