PSE 2018 error message about trial version

[SAL1313]

I have PSE 2018 which has worked until yesterday afternoon (worked in the morning). I tried to open again and I'm getting a message about a trial version, asking if I want to download or sign in. It won't accept my info. I tried exporting from Lightroom and get same message. I went into my account, tried to enter my Serial Number and get a message that it's already used. Any advise on what I should do?

[Akash Sharma]

Hi there,

Sorry that Photoshop Elements and Lightroom showing up as trial and no longer accepting your serial number. Would you mind checking out this article https://helpx.adobe.com/in/creative-suite/kb/error-serial-number-valid-product.html and let us know if that helps? 

Thanks,

Akash