Activation/Deactivation problem Audition 2.0

I have a license Audition 1.5 and an upgrade license to Audition 2.0.
I tried to install Audition 1.5 in Windows 11, but as soon as I install the upgrade to 2.0, it already fails during the installation.
In my Windows 10 PC I had already deactivated Audition 2.0 about 5 years ago and now it is no longer possible to activate this version.
I get the message 'Activation server unavailable' and if I want to activate by telephone (31) 020 201 3805 I get the message that this number is out of service.
To ask:
1. How do I activate/deactivate my Audition 2.0 on my Windows 10 PC?
2. How do I activate/deactivate Audition 1.5 and the upgrade to 2.0?