Can we ask for these information just to further check on the issue: - At which site are you receiving this problem? - Which internet browser? (Firefox, Google Chrome, etc)
For normal troubleshooting, please try restarting the Password Manager's components. You can open the Password Manager Diagnostic Toolkit and click on "Stop All Components".. after a short while, click on the "Start All Components".
Please also try using the Password Manager extension on other internet browsers that you have and let us know the results.