Changelog v4.5.0:
#Fixed: spawn cancelling for players in enabled worlds stopped spawning completely until reconnect.
Please note that MC 1.16.5 has little to zero impact on plugins working on MC 1.16.4. That is why this and all of my other plugins are just fine with running on MC 1.16.5.
Best regards
Alex_qp
PS:
@baconsmoothie thank you for providing your debug logs.