Seconded. Exact behaviour. I’m in a Pro plan as well and I used Spark last week, but when I try to use it now, even with /status showing me 100% available, I’m receiving the same error in cli:
Model metadata for gpt-5.3-codex-spark not found. Defaulting to fallback metadata; this can degrade performance and cause issues.
■ {“type”:“error”,“status”:400,“error”:{“type”:“invalid_request_error”,“message”:“The ‘gpt-5.3-codex-spark’ model is not supported when using Codex with a
ChatGPT account.”}}