‘message’ => ‘Invalid user ID.’

When users attempt to register they get an error message:

array (
  'message' => 'Invalid user ID.',
  'dump' => 
  array (
    'ID' => 0,
    'display_name' => ' ',
  ),
  'changes' => 
  array (
    'form_id' => '996',
    'custom_fields' => 'a:6:{s:10:"user_login";a:15:{s:5:"title";s:8:"Username";s:7:"metakey";s:10:"user_login";s:4:"type";s:4:"text";s:5:"label";s:8:"Username";s:8:"required";i:1;s:6:"public";i:1;s:8:"editable";i:0;s:8:"validate";s:15:"unique_username";s:9:"min_chars";i:3;s:9:"max_chars";i:24;s:8:"position";s:1:"1";s:6:"in_row";s:9:"_um_row_1";s:10:"in_sub_row";s:1:"0";s:9:"in_column";s:1:"1";s:8:"in_group";s:0:"";}s:10:"user_email";a:13:{s:5:"title";s:14:"E-mail Address";s:7:"metakey";s:10:"user_email";s:4:"type";s:4:"text";s:5:"label";s:14:"E-mail Address";s:8:"required";i:0;s:6:"public";i:1;s:8:"editable";i:1;s:8:"validate";s:12:"unique_email";s:8:"position";s:1:"4";s:6:"in_row";s:9:"_um_row_1";s:10:"in_sub_row";s:1:"0";s:9:"in_column";s:1:"1";s:8:"in_group";s:0:"";}s:13:"user_password";a:16:{s:5:"title";s:8:"Password";s:7:"metakey";s:13:"user_password";s:4:"type";s:8:"password";s:5:"label";s:8:"Password";s:8:"required";i:1;s:6:"public";i:1;s:8:"editable";i:1;s:9:"min_chars";i:8;s:9:"max_chars";i:30;s:15:"force_good_pass";i:1;s:18:"force_confirm_pass";i:1;s:8:"position";s:1:"5";s:6:"in_row";s:9:"_um_row_1";s:10:"in_sub_row";s:1:"0";s:9:"in_column";s:1:"1";s:8:"in_group";s:0:"";}s:10:"first_name";a:12:{s:5:"title";s:10:"First Name";s:7:"metakey";s:10:"first_name";s:4:"type";s:4:"text";s:5:"label";s:10:"First Name";s:8:"required";i:0;s:6:"public";i:1;s:8:"editable";i:1;s:8:"position";s:1:"2";s:6:"in_row";s:9:"_um_row_1";s:10:"in_sub_row";s:1:"0";s:9:"in_column";s:1:"1";s:8:"in_group";s:0:"";}s:9:"last_name";a:12:{s:5:"title";s:9:"Last Name";s:7:"metakey";s:9:"last_name";s:4:"type";s:4:"text";s:5:"label";s:9:"Last Name";s:8:"required";i:0;s:6:"public";i:1;s:8:"editable";i:1;s:8:"position";s:1:"3";s:6:"in_row";s:9:"_um_row_1";s:10:"in_sub_row";s:1:"0";s:9:"in_column";s:1:"1";s:8:"in_group";s:0:"";}s:9:"_um_row_1";a:5:{s:4:"type";s:3:"row";s:2:"id";s:9:"_um_row_1";s:8:"sub_rows";s:1:"1";s:4:"cols";s:1:"1";s:6:"origin";s:9:"_um_row_1";}}',
    'mode' => 'register',
    'core' => 'register',
    'use_custom_settings' => '',
    'timestamp' => '1542144904',
    'request' => '',
    '_wpnonce' => '96cca73297',
    '_wp_http_referer' => '/register/',
    'user_login' => 'Mike',
    'first_name' => 'mike',
    'last_name' => 'oberdick',
    'user_email' => '[email protected]',
    'user_password' => 'Mike1224',
    'confirm_user_password' => 'Mike1224',
    'submitted' => 
    array (
      'form_id' => '996',
      'timestamp' => '1542144904',
      'request' => '',
      '_wpnonce' => '96cca73297',
      '_wp_http_referer' => '/register/',
      'user_login' => 'Mike',
      'first_name' => 'mike',
      'last_name' => 'oberdick',
      'user_email' => '[email protected]',
      'user_password' => 'Mike1224',
      'confirm_user_password' => 'Mike1224',
    ),
    'role' => 'subscriber',
  ),
)

Here is the install log

Any idea about what’s happening?

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