Customizer not working

Hi, I did a fresh install of WordPress, installed your theme and the customizer doesnt load and shows this fatal error: The web page at https://www.mindfieldwellness.net/wp-admin/customize.php?theme=astra&return=https%3A%2F%2Fwww.mindfieldwellness.net%2Fwp-admin%2Fthemes.php might be temporarily down or it may have moved permanently to a new web address.
ERR_HTTP2_PROTOCOL_ERROR
When I activate another theme the customizer works perfectly. How can I fix this? please help!!!! Been stuck for days and even did a fresh WordPress install to pinpoint the bug which is coming from your theme.
Thanks!

The page I need help with: [log in to see the link]