How Can I Activate Adobe Photoshop Elements 2020 on My New Computer When it Won't Let me!?

I have already logged out of my old device. i have installed Elements 2020 on my new computer, but it keeps saying “The serial number is already in use by the maximum allowed computers. You need to deactivate another computer within 30 days to use this product.” I already did! How can I make my new computer believe me? I have reached out to support and they were of no use. I looked at my plans and products under manage my account and none are listed. Please help me!