Thank you for your quick response.
I have tested with a computer that according to the configuration is capable. The client in question is a dell laptop with windows 10.
However in the capture it looks like neither the access point nor the laptop advertise this capability, see attachade picture:
1. Probe request, Client > AP (does not contain RSN capabiliteis)
2. Probe Response, AP > Client: contains RSN capabilites but MFP capable is "False"
...
23. Association request, Client > AP: contains RSN capabilites but MFP capable is "False"
I am looking in to the client side as well. We have windows, apple and linux laptops.