Laravel session token create new file

I'm using Laravel session's 'file' driver and adding sessions according to my requirement.

For some reason, I have noticed its creating several consecutive session files per second have data in like this

Session File1

"a:2:{s:6:"_token";s:40:"x7aF98HJm0pXuWM0bCvawX7Z2C7wxiGcUQcvXGSX";s:6:"_flash";a:2:{s:3:"old";a:0:{}s:3:"new";a:0:{}}}"

Session File2

"a:2:{s:6:"_token";s:40:"1QNFVXY9vsZYiuPQghk07R0Y9LUPQZ7ZWeU25TbQ";s:6:"_flash";a:2:{s:3:"old";a:0:{}s:3:"new";a:0:{}}}"

Each file have a different token value but doesn't have any session key created by me. I don't know how are these files being created. And, this data doesn't contain any relative session that I have created.

Could you please suggest why it's creating a number of these partial session files.

via Chebli Mohamed