Issue with token based authentication in shared hosting

I am working on a WEB API project where I am using token based authentication.

In my local machine, it is working fine.

But when I deploy it to a shared web hosting, tokens are generating but after sometime, I am getting below message while accessing APIs. I set expiration of token for 1 month.

{

"Message": "Authorization has been denied for this request."

}

401: Unauthorized

When I googled, I see about machine key in tokens. But I didn't understand it completely.

Can you please tell me what may be the issue?

Thanks and regards,

Santhosh Simha