Can't activate the plugin

[pedro-rivera]

When I try to activate the plugin, the panel returns the following and the panel gets all messy 😕

Warning: call_user_func_array() expects parameter 1 to be a valid callback, function 'register_fields_rgba_color' not found or invalid function name in C:\wamp\www\barcompany\wp-includes\plugin.php on line 496

[younes0]

I get the same message but the plugin actually works.
I had to comment acf-rgba-color.php@34
// add_action('acf/register_fields', 'register_fields_rgba_color');