|The QoS question was did you setup Qos which apparently you have not so its not an issue.|
Question concerning same ip address was for you to check each device to see if its getting the same ip address as in your routers dhcp is only providing one ip address hence only one piece of equipment can connect at one time.
Who setup the router?
What make and model is it?
Has this ever worked to have multiple devices connect via wifi?
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