Photoshop CS6 turned into a "Tryout" trial version

[ssanboo]

Hi there!

I've owned the CS6 versions of Photoshop/InDesign/Illustrator since 2012, back when they came on a disc in a box. My sister bought it for me, and not from any shady third party seller. 

I changed my CC plan from All Apps to just Photography recently because I couldn't afford it anymore, as I figured I could use my old CS6 programs. But now whenever I try to launch the CS6 version of Photoshop (and any other CS6 program), a message pops up saying "Your trial will expire in x number of days." This never happened when I was on the All Apps tier. Has anyone dealt with this before? I do need to use these programs for work, so I'm a little worried that Adobe won't let me use the CS6 programs once this "trial" period expires. But I own the programs! I'm confused haha. 

I'm on High Sierra, and the "Tryout" versions of the programs work perfectly fine, so I don't think it's an OS issue. 

Thanks in advance for any and all advice!

[Peru Bob]

Did you try entering your serial number?

[ssanboo]

Hi! I did try when I was trouble-shooting myself, and I clicked through to "License this software". 
Unfortunately a message came up that said "The serial number you entered is invalid". It should be the same serial number that came with the box, so I'm not sure what's going on there. 

[Peru Bob]

The serial number you entered is invalid

By @ssanboo

See here:

https://helpx.adobe.com/x-productkb/global/invalid-revoked-serial-numbers.html

and here:

https://www.adobe.com/genuine/landing-dnr.html?promoid=791Y6S4Z

[ssanboo]

The software was purchased from an official retailer so the serial number issue puzzles me, but thank you for the links. I'll keep looking into it.