Azure IoT Central V3 connector's dynamic content doesn't locad with error message In case using new UI Logic App designer and editing specified region such as West US 2

[ShingoHanai]

Describe the Bug with repro steps

1. Create new Logic Apps in West US 2.
2. Switch new UI Logic Apps designer.
3. Choose a action such as Update Device Properties of Azure IoT Centaral V3 connector.
4. You can see error message 'The response is not in a JSON format.' in drop down menu.
   

What type of Logic App Is this happening in?

Consumption (Portal)

Are you using new designer or old designer

New Designer

Did you refer to the TSG before filing this issue? https://aka.ms/lauxtsg

Yes

Workflow JSON

No response

Screenshots or Videos

No response

Browser

Google Chrome, Microsoft Edge

Additional context

This error doesn't occurr in other region such as Japan East or using old UI designer.
In infrastructure logs, I found 503 backend responce in APIM.

[preetriti1]

@ShingoHanai - Do you mind sharing the screenshot of error response on teh call you see 503 response?