Example of post-workflow step calculations

functions.php

<?php
add_action( 'gravityflow_post_webhook', 'sh_action_gravityflow_post_webhook', 10, 4 );
function sh_action_gravityflow_post_webhook( $response, $args, $entry, $current_step ) {
	//Replace step ID and fields for calculation to match your use case.
	if ( $current_step->get_id() == 77 && is_numeric( $entry['3'] ) && is_numeric( $entry['16'] ) ) {
		$entry['14'] = round( $entry['3'] * $entry['16'], 2);
		$result = GFAPI::update_entry( $entry );
	}
}

Your snippet is modifying the $entry which is not part of $response which is what the filter returns back to the rest of Gravity Flow for processing. You use the GFAPI to update the entry, but it is most likely that Gravity Flow would use the values in $response after your filter runs to update the entry. The doc you linked to provides good examples of how your code should be structured or you may want to review https://developer.wordpress.org/reference/functions/add_filter/ as both issues are concepts that the core of WP approach to hooks covers.

• Modify $result instead of $entry
• Ensure your filter returns $result instead of using the GFAPI.
• Your goal seems to be unrelated to the filter of this snippet. Vendor support might be a better place to ask follow-ups.

Hello again
Thank you very much
I was submit in there and if it will be solved, ill share it for sure!
If you dont like my comments to be here, im sory for that an i can delete them quiekly
Thanks again and Good Bye.