Hello @UglyDuck 

Thanks for the report, here are some tips that might help fix the ' There is a problem' on Alexa error for you. 

• Confirm Kasa APP and device firmware are both up to date
• Confirm Alexa app is up-to-date. 
• Remove device in the Alexa app and rediscover device :  Use voice command "Alexa, discover devices". Alexa will scan and show the devices bound to your Kasa account.
• Disable Kasa Skill and relink kasa device in your Alexa APP

Here is an instruction for device control problem in Alexa app that might help : What should I do if I cannot make my Kasa device work with Alexa or Google Home? 

We fixed a similar problem back in Nov 2021 as mentioned old thread, while the error does not have a specific meaning, if the problem persists despite the above steps,  we will check to see what's going on again, kindly help provide some case details, thank you

• MAC address of kasa device ( please share via private message)
• TP-Link ID  email account ( please share via private message)
•  a photo of error

  @UglyDuck 
Thank you for the reply, glad to know that removing the kasa device and rediscover device helps fix the issue,  it might be a glitch on the device or something like a delay or lag in the network, you could observe the performance of the kasa bulbs for now. Feel free to share a photo and MAC address of your device if this occurs again.