With the external view to the street, situation is quite complicated. Noises inevitable.

The system led on the camera is solid green? Is there security setting on your router like MAC filtering or access control? Check network connection on the web page:...

Your firmware is latest? Seems issue not resolved. Email tplink to fix it

If VPN passthrough is enable but doesn't work, I think you can email tplink support to fix it.

150826 can be found there https://www.tp-link.com/au/download/Archer-D9.html#Firmware If you cannot downgrade, contact tplink support. Sometimes if your firmware is EU version, it cannot downgrade to...

If someone is taking too much bandwidth, what you need to do is bandwidth control, or IP qos. Not every tplink router support that. If it's simply slow with no one downloading files, then check the...