Array Error

When entering shortcode [wp-prayer-engine] on a WordPress Page, I get the following error:
Warning: in_array() expects parameter 2 to be array, string given in /home/customer/www/SITENAME.com/public_html/wp-content/plugins/wp-prayer/wp-prayer-engine.php on line 126

This is the corresponding line:
if (in_array(‘form’, $atts) && array_key_exists(‘type’, $atts)) {

I am not familiar with PHP coding, can you please advise on how to correct the error?

The pages appears to function and post but prompts with this error message.
I am currently using Version 1.6.7.

I would try WP-Prayer II but I didn’t see any instructions on shortcodes once installed.