After digging through hundreds of forum posts and technical documentation, the 80001fff error almost always points to one culprit:

Go into your router’s settings, find the IPv6 toggle, and turn it OFF . Restart both your PlayStation and your device. This forces everything onto the simpler, more stable IPv4 protocol. Remote Play loves IPv4.

Because sometimes, the ghost just needs to be rebooted. Have you battled the 80001fff? Did the microwave trick work? Let the community know in the forums—and may your next remote play session be error-free.