Thank you for your post Kian9910 and welcome to our community.
Could we please confirm if you're able to connect the Xbox through an ethernet connection? As we recommend this for the most stable connection possible.
In regards to your 5Ghz connection, if all of your devices are on one channel this could then slow the 5Ghz channel down and you'll experience some issues as it can only handle so many connections depending on what broadband speed you're subscribed to. For the best WiFi usage you can connect devices further away from the Hub to the 2.4Ghz connection and devices closer to the Hub to the 5Ghz connection.
I'll also include some links to our WiFi Help page and our WiFi Forum page which may offer further tips to help your connections.
Thank you, Emily.