Hi @Debbaut, Niels
Great to know that the issue has already been resolved and thanks for sharing the solution so that others experiencing the same thing can easily reference this! Since the Microsoft Q&A community has a policy that the question author cannot accept their own answer. They can only accept answers by others, I'll repost your solution in case you'd like to Accept the answer to help more users who encounter the same problem.
Case title: I am unable to select saterday and sunday in teams planner as due date**
Issue Symptom: I have a shared Microsoft planner in our teams. When I try to set a due date of a project on Sunday, it automatically jumps to Monday. Seems like I need to adjust the workweek but I cannot see where. After some research I cannot find much information about this topic.
Resolution:
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