Password Incorrect Error

Need help here pls?

I always received my payslip in password protected pdf format. Only today its happening first time that when ever i am trying to enter the password(only numbers) it popping up an error," password Incorrect, please try again". I have tried using the same on Chrome and Edge both but its not working at all. Only time it worked when i downloaded the attachment and enetred my password. But whenever i just click on attchment to open it using password, it not working.

Does anyone knows why? Any solution to this?

Note: its happening at my laptop but working on my Android phone 

Thanks