WePay all of a sudden stop working?

I am getting this error now. It was working fine but now its not popping up my when I submit to fund. BTW, my application is fully live.

Fatal error: Uncaught exception ‘WePayPermissionException’ with message ‘this access_token has been revoked’ in /home/…………/public_html/wp-content/themes/dev_funding/funding/lib/WePay/wepay.php:268 Stack trace: #0 /home/…………/public_html/wp-content/themes/dev_funding/funding/lib/WePay/wepay.php(290): WePay::make_request(‘preapproval/cre…’, Array, Array) #1 /home/…………/public_html/wp-content/themes/dev_funding/funding/funding.php(507): WePay->request(‘preapproval/cre…’, Array) #2 [internal function]: F_Controller->action_template_redirect(”) #3 /home/…………/public_html/wp-includes/plugin.php(525): call_user_func_array(Array, Array) #4 /home/…………/public_html/wp-includes/template-loader.php(12): do_action(‘template_redire…’) #5 /home/…………/public_html/wp-blog-header.php(16): require_once(‘/home/devsponso…’) #6 /home/…………/public_html/index.php(17): require(‘/home/devsponso…’) #7 {main} thrown in /home/…………/public_html/wp-content/themes/dev_funding/funding/lib/WePay/wepay.php on line 268