Persistent HTTP 400 INVALID_ARGUMENT – Account stuck for 24+ hours, all models affected (macOS)

I’m on Google AI Pro and Antigravity has been broken for me since yesterday.

Every model dies on the first message — Gemini 3.1, Flash, Claude, doesn’t matter. Sign out, sign back in, it works once, then gone again. I’ve pulled Antigravity’s access from my Google account and re-authenticated twice. Same result.

Trajectory ID: dcc7dd99-5423-4ba9-9300-467d6c6fd6b4

Other threads here point to the GCP project ID not binding correctly server-side. Nothing local fixes it. Can someone look at my account and reset whatever’s stuck?