In Architect, flows authors set a default language for the flow. If a language is not set on a call, then the default language set on the flow will be used. However, when a call comes in on an Edge line for which a language is configured, the Edge line sets the language on the call. 

A flow will run in the Edge trunk line’s configured language if:

• The default language configured for your flow differs from the default language configured for your Genesys Cloud Edge trunk line, and
• The flow includes the line’s default language as a supported language.

Architect does not return these errors in flow validation. Calls associated with the flow will execute properly, but run in the Edge line’s default language. To prevent this issue, ensure that your Edge line’s default language is included in your flow’s supported language list. For more information on Edge trunk lines and selecting a flow’s supported language, see the Suggested content.