Hello Jan van de Glind,
In mendix 10 deeplink module has been deprecated ,need to understand after upgrading from version 8 to version 10,are you still using old deeplink module?
In version 10 we need to handle it in other way MF url /page url.
then we need to make the final url as below to land on specific page.
https://abc-accp.mx.lowcode.cloud/SSO/login?cont=p/AccessRequest/
Ik solved my problem. Because I know the user and password, I show a dark screen with a Microflow Timer and call the nanoflow ACT_Login. This will open a user session.