@Fae and @Hank21, over to you - we're running out of ideas here. Bug in firmware?

@TiagoLoss Can you try to set Usernam as '123' or something without a special character? Not required anyway but filed must not be empty. Field 'Domain Name' looks a bit short to me - although...

@TiagoLoss Strange. Can I see the whole Update URL and config of service in detail?

+1

@LarsK1 Which router model and installed firmware version we're talking about?

@joeWDC Yes - go for latest BETA software for ER605 v2 which you can find here: https://community.tp-link.com/en/business/forum/topic/599910 Connect/Disconnect issues should be resolved. But please...