The Plan Mode Won't Implement When Using Azure AI Foundry Model

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Bug

Copilot Feature Area

Copilot Agent Mode

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Hi, I am facing an issue with a github copilot on the plan mode, I am using a model GPT-5.2-Codex and GPT-5.3-Codex from Azure AI Foundry, during planning everything is working smoothly but when I click the start implementation it wont implement the plan, I am not sure what cause this issue.

The output will look like something like this, "I’m currently in Plan mode only, so I can’t execute file edits in this turn.", Even I already change the mode to agent mode manually the LLM wont implement the plan, but when I change the model that provided from the Github copilot it will works again. The issue only occur on Azure model.

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