Be sure Yi iot app and camera is working.
And enable‘Enable Camera Stream’ of Echo show in the setting page.
Below is my camera name ‘Smart camera’.

Login echo show (amazon account).

Setting on echo show. My setting below:
–region: Europe
–time: Paris, France, Central European Summer Time
–language: English (UK)

Login alexa app and search skill ‘yi iot’. Be sure Echo show and alexa app are the same login account. (amazon account).
Then enable skill and link account, the country and account must be same on Yi iot app.

After link your account, discover device in alexa app.
Be sure camera is discovered.
Be sure echo show is online. Below is my device list and echo show device name.

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