Error message

• Warning: Cannot modify header information - headers already sent by (output started at /var/www/website/html/includes/bootstrap.inc:1692) in drupal_send_headers() (line 1551 of /var/www/website/html/includes/bootstrap.inc).
• TypeError: Argument 1 passed to date_granularity_precision() must be of the type array, null given, called in /var/www/website/html/sites/all/modules/date/date.theme on line 79 in date_granularity_precision() (line 1665 of /var/www/website/html/sites/all/modules/date/date_api/date_api.module).