@Onurk Hi Onur,

Thank you for valuable information.  

If Wi-Fi connected but no Internet, please log in to tp-link management page, and change the Wi-Fi channel to1.6.11; Channel width to 20Mhz and see if this helps:

https://www.tp-link.com/support/faq/1417/

If still the same issue, can you help confirm some information on this issue. 

When this issue occur, did WPA7510's Wi-Fi signal disappear , or Wi-Fi signal still there, but Wi-Fi client lost Internet?

For example Wi-Fi but no Internet, or Wi-Fi report some Error message? Do you need to reconnect to Wi-Fi signal to reconnect to recover Internet?

@Onurk Hi Onur, 

If Wi-Fi signal is totally gone on all your devices, this could be a hardware issue on Wireless adapter. 

You could perform a reset with it powered on and use a pin to reset hole for 10 secs, after that repair2 units. 

If this did not resolve the issue, wireless adapter should be faulty, please contact retailer or local support to check warranty.