Fatal error: Uncaught Error: Call to undefined function _date_api_element_info()

When my site running for a week later,I got the following errors:

Fatal error: Uncaught Error: Call to undefined function _date_api_element_info() in
D:\xampp\htdocs\test\sites\all\modules\date\date_api\date_api.module:2448 Stack trace:
#0 D:\xampp\htdocs\test\includes\module.inc(957): date_api_element_info()
#1 D:\xampp\htdocs\test\includes\common.inc(6485): module_invoke_all('element_info')
#2 D:\xampp\htdocs\test\includes\common.inc(6022): element_info('html_tag')
#3 D:\xampp\htdocs\test\includes\common.inc(6059): drupal_render(Array)
#4 D:\xampp\htdocs\test\includes\common.inc(355): drupal_render(Array)
#5 D:\xampp\htdocs\test\includes\theme.inc(2914): drupal_get_html_head()
#6 D:\xampp\htdocs\test\includes\theme.inc(1125): template_process_maintenance_page(Array, 'maintenance_pag...')
#7 D:\xampp\htdocs\test\includes\errors.inc(254): theme('maintenance_pag...', Array)
#8 D:\xampp\htdocs\test\includes\bootstrap.inc(2604): _drupal_log_error(Array, true)
#9 [internal function]: _drupal_exception_handler(Object(Error))
#10 {main} thrown in D:\xampp\htdocs\test\sites\all\modules\date\date_api\date_api.module on line 2448

My environment: Windows Server 2008, XAMPP with PHP 7.1.1.

Thanks.