@Jan_Linhart,
As an administrator of the GlobalProtect Portal, you can limit the number of times that a user can disable the GlobalProtect agent in the Client App configuration tab. It's not something enabled by default, as most organizations will simply choose which disable method they wish to allow, if any, and won't enable any sort of count limit.
It looks like your organization has chosen to set this option and only give each user X number of agent disables. You'd have to reach out to them to get them to clear this or reset your count.
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