This is normal: there’s no action needed on your part.
The “Not Applicable” just means that your website doesn’t have enough user interaction data from real-world mobile/desktop users (mobile in your case) over the latest 28-day collection period for Google PSI to provide responsiveness metrics for your website.
Nothing to worry about (other than to get more visitors to your website).
As far as I know, the message from Google PageSpeed means that there is too little data for an analysis. For Core Web Vitals, the views of your page by chrome-based browsers are used. If you don’t have enough visitors using Chrome, the data is missing.
You should be able to ask for details about this in the Google Search Community: https://support.google.com/webmasters/community?hl=en – this is not really a topic for WordPress.
