POST /order always 400 "Invalid order payload" — Gnosis Safe account, everything looks correct

[NorrenZheng]

Hey,

I've been testing order placement via the API and keep getting
{"error":"Invalid order payload"} on POST /order with a Gnosis Safe proxy.

My setup:

• EOA: 0xF789a79b... (full address via DM if needed)
• Safe (proxy): 0xCF98B6bF... (full address via DM if needed)
  Gnosis Safe v1.3.0, Polygon mainnet
• signatureType: 2 (POLY_GNOSIS_SAFE)

Verified:

• CTFExchange.getSafeAddress(EOA) returns the correct proxy ✓
• Safe.isOwner(EOA) = true ✓
• ecrecover(signature) = EOA ✓
• Balance verified on-chain ✓
• Active market token, accepting orders ✓
• Tried signatureType 1 and 2, same 400 both times

Also noticed: getPolyProxyWalletAddress(EOA) returns a different
address — not our Safe. Is that expected for Gnosis Safe accounts?

Is there extra setup needed on the CLOB side for Safe wallets?
Related to #339?

Thanks