Laravel: Carbon stop working after several hours

I've faced very strange behavior of Laravel 5.3 on PHP7/Apache (Windows).

My application is working perfect for several hours, but in unpredictable moment site crashes with errors like:

• Symfony\Component\Debug\Exception\FatalThrowableError: Call to undefined method DateTime::format() in C:\site\telemed\bootstrap\cache\compiled.php:14049
• Symfony\Component\Debug\Exception\FatalThrowableError: Call to undefined method Carbon\Carbon::modify() in C:\site\telemed\vendor\nesbot\carbon\src\Carbon\Carbon.php:1806
• and so on...

Also found in Apache Error Log:

Cannot make non static method DateTime::b\x10Y7I\xc0\xf1\xbdff() static in class DateTime It looks like PHP forgets about some part of system code... Carbon stops working even in Monolog.

After Apache restart things get normal. Or sometimes it can get normal without any actions after ~30mins.

Any ideas what is happening?

Thank you in advance!