Rekordbox ver.5 license key problem

Hello everyone! 

My first question is, does the hardware unlock on rekordbox 6 when hardware is connected (DDJ400) work exactly the same as rekordbox 5 with the license key entered, but are there any differences?

My second question - basically a problem

I want to use my key I got from the DDJ400 in rekordbox 5 as I wouldn't want to lose it but I deactivated the old key after selling the DDJ-RB but there is still a deactivation button there and when I click it I get error number 22 preventing me from typing a new one license key, any ideas for a solution? I want the account I currently have.

Thanks in advance for all answers !!! <3 

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