I also don’t see them in Chrome on my iPhone. I do see them if I try to emulate a phone in Chrome on my desktop. I don’t know why they wouldn’t be showing up. It’s possible that there might be a conflict with one of your current plugins or your theme.
Try disabling all of your plugins except WP Job Manager (and add-ons). Then try testing again to see if the issue persists. If that resolves your issue, you can find what was causing it by enabling each plugin one by one while continuing to test.
If that doesn’t help, you can also try switching to the Twenty Sixteen theme via Appearance > Themes, and test again. If the issue is resolved then you know it’s a problem with the theme, and you’ll need to contact the theme author for further assistance.
You might want to do this on a staging copy of your site. Many hosts provide a staging service, where you can do testing without affecting the live site. You can ask your host about this. If they don’t give you a staging site, you could try WP Staging or Duplicator:
https://www.ads-software.com/plugins/wp-staging/
https://www.ads-software.com/plugins/duplicator/
Let me know what you turn up!