Dsl3890 Firmware Link -

It is highly recommended to perform a "Factory Reset" after a major firmware update. This clears out old configuration files that might conflict with the new code. You can do this by holding the reset button on the back of the router for 10 seconds while the device is powered on.

If your router is already bricked (stuck in a boot loop), you can force a firmware flash via TFTP. dsl3890 firmware link

You should always download firmware directly from official sources to avoid compromised files. The primary repository for this model is the D-Link Australia Support Resource Direct Firmware Directory: It is highly recommended to perform a "Factory