1. Check your settings in your web-editors or other programming tools to ensure that the correct font and font size are applied.
2. Look through the source code on your web page, if your font and font size is specified in the code then make the necessary changes to the font style or size.
3. Check your CSS to make sure that the font-family and font-size declarations are set correctly.
4. Validate your HTML and CSS to check for any potential problems with your code.
5. If your source code or CSS specifies one font, but a different font is being rendered on the page, try specifying a font family, which will cause browsers to render the correct font.
6. If all else fails, consider using online tools such as Font Stack to get the CSS code needed to ensure the correct font is displayed.