In all clarity and honesty, it’s the T5577 chip which is to blame. A shit coupling between it and the writer is what brings the issue out however. In short, the T5577 has no tear protection, and a bad coupling or a writer with bad signal timing can introduce errors into the configuration bytes of the T5577 which render it so badly misconfigured that is fails to communicate properly. A longer explanation can be found here; https://forum.dangerousthings.com/t/quirks-of-the-t5577-cloning-tags-to-the-xem
The good news is, a proxmark3 can usually resolve the issue by sending test mode commands to the T5577 to wipe and reset it… usually.