why update option is not working?

by 

update_option('acp_cf_settings' , array('acp_cf_status'=>$resp['status']));
update_option('acp_cf_settings' , array('acp_cf_log'=>$resp['log']));

You are overwriting the setting. After the second update_option call there is no acp_cf_status key anymore for the array variable, just the acp_cf_log.

Just to be clear, you would need something like this:

update_option( 'acp_cf_settings', array(
    'acp_cf_status' => $resp['status'], 
    'acp_cf_log' => $resp['log'],
) );