How do you activate your Trados SDL license when you are switching computers?

I have recently had to change laptops because mine was very old. However, my SDL Trados 2021 was installed in my old computer. I tried reinstalling it in my new computer using the activation code I previously used, but apparently it is 1 use only. 

Disclaimer: I am not trying to use the software in multiple computers at once, or trying to "give" it to someone else. I am merely trying to switch the software from my old computer to my new one, and since my license was "for life", I figured there must be a way to transfer the software and reactivate it in new laptop, I just don't know how.

Anyone got any clues?

Thank you in advance.

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