Issue activating licence, error 26:Request denied due to clock tamper detection:LSRequest

Hello,

Hello,Regarding the upgrade (2019 license to 2021 license) and the installation of Trados Studio 2021, we encountered a problem when we tried to activate the license, a pop up appeared with the following error:
Error 26: Request denied due to clock tamper detection: LSRequest
And the license was locked as if already in use and we are unable to deactivate it to try again.

So after requesting help from the support services, we tried again by following the different steps available here (https://gateway.rws.com/csm?id=kb_article_view&sysparm_article=KB0033086) but with the directory file C:\ProgramData\Package Cache\SDL\TradosStudio2021SR2.
We have even tried to replace the folder with an installation without issue and activate the licence off-line.

Would you be able to assist us any further regarding this technical problem?