Device is not responding

[michezefix]

Hey, so I know this issue was already mentioned a couple of times. But none of the fixes I found so far worked for me.
I've set up a sketch to control two lamps in my room. But every time I tell Alexa (Gen3 Echo Dot) to turn one of the lamps on, she answers with 'the device is not responding', although the lights already turned on with the correct brightness. I already tried fauxmoESP and got the same results. The fixes i found so far are:

• no long delay in the main loop (which is not the case with my code)
• c1e8f1d
  and this piece of code from 2019, which is already implemented in the 2021 version of the library

Is there any solution to this problem or an alternative that i can use? I really don't want to buy any controllers, since DIYing is just so much more fun.
Thanks in advance for your help!

Here's the code I'm using:
tv_controller.zip