Accompanying Files
Observation Details
Headings "MagentaMobil Prepaid Tarife" (<h1>) and "Rufnummer vom Wettbewerber mitnehmen und 10 € Wechselbonus sichern.*" (<h2>) are not visually identifiable as headings.
Instead, non-heading text content (<p>) is used as the actual visual heading.
Beware, heading structure / outline of a page is very much the most used method for screen reader users to navigate web pages. See WebAIM Web Accessibility Survey, making a good outline the absolute basis of delivering an accessible web page.
Remediation Notes
Only use heading elements (<h1>, ...) for text content that is also displayed and used as a heading. Always use heading elements for such content.
If it looks like a heading, make it a heading. If it does not look like a heading, do not make it a heading.
Tip for Content Management: Start by looking at the page content without any styling. Ensure a fitting heading structure / outline and also ensure that all content is appropriately introduced by its heading.