not saving changes AND highend options page is wonky

the Highend options page is not displaying properly (see screenshot) and although it appears that I can still make changes, they do not save. previously everything worked, but of course I’ve made two changes.

First I’ve migrated this installation to a new wordpress install on a new webserver, by using “All-in-One WP Migration” software, and the website appears exactly as it was on the old webserver, and everything functions properly on the admin side except for Highend options. I have verified the php.ini memory limit is 512M, max_execution_time is 400s, max_input_time is 300s, the wp-config.php memory_limit is 256M, and set_time_limit is 400.

Second, after this migration (and before looking at Highend options, so I don’t know what caused the problem), I updated the Highend theme v2.4.4 through the update button that appeared over the theme in WordPress, and it did not update the current theme but rather installed a SECOND Highend theme v3.7.3 beside it. It’s worth noting that I have always used Highend Child theme v1.0.0 as my active theme, but I have the exact same results (in Highend options) when I switch active theme to either of the two versions listed.

How can I go about troubleshooting?