It sounds like you have correctly set up Google Tag Manager and GA4 for your single page application, but are having trouble seeing the page views in your network. There could be various reasons for this issue. It could relate to certain blockers, e.g., ad blockers or privacy extensions that might prevent the correct data from being sent to Google Analytics. Another reason could be incorrect or conflicting set ups in GA4 and GTM. For example, make sure your GA4 configuration tag in GTM is correctly set up to fire on all pages or accordingly to your desired triggers. Also check your triggers, variables and tags; they should be properly configured. If the configuration is correct but you’re still having issues, it may be beneficial to seek professional help or reach out to Google support.