Comment Box on Tasks in Microsoft Planner is not working / responding

I have used both Basic and Premium subscription to create Plan. The comment box in task does not allow me to type anything. It seems inactive.
I have created all the plans for groups, So the group members can access it. I have created a task and assigned myself as well as one other person. Surprisingly he can comment through comment box, but I still can not.
There are no access rights issues because i am the group owner and teams admin.
I have no idea, why for the same task I

I have used both Basic and Premium subscription to create Plan. The comment box in task does not allow me to type anything. It seems inactive.
I have created all the plans for groups, So the group members can access it. I have created a task and assigned myself as well as one other person. Surprisingly he can comment through comment box, but I still can not.
There are no access rights issues because i am the group owner and teams admin.
I have no idea, why for the same task I can not comment and others can. I have tried different browsers and Teams but still did not able to find any solution.

can not comment and others can. I have tried different browsers and Teams but still did not able to find any solution.