Hi @ch1n3s3b0y
You’ve done some great testing!
I can’t say why update_field would not work for you.. the parameters looks correct to me.
However instead of a custom $wpdb update you can try using WP cores update_post_meta()
function. It will essentially do the same thing as update_field()
.
https://codex.wordpress.org/Function_Reference/update_post_meta