diff --git a/packages/api/src/car.js b/packages/api/src/car.js
index e2e6146f8b..c127f45d0f 100644
--- a/packages/api/src/car.js
+++ b/packages/api/src/car.js
@@ -121,7 +121,7 @@ export async function handleCarUpload (request, env, ctx, car, uploadType = 'Car
   const carCid = CID.createV1(CAR_CODE, await sha256.digest(carBytes))
   const s3Key = `raw/${sourceCid}/${user._id}/${toString(carCid.multihash.bytes, 'base32')}.car`
   const r2Key = `${carCid}/${carCid}.car`
-  env.sentry?.setExtras({ sourceCid, carCid, dagSize, structure, s3Key, r2Key })
+  env.sentry?.setExtras({ sourceCid, carCid: carCid.toString(), dagSize, structure, s3Key, r2Key })
 
   await Promise.all([
     putToS3(env, s3Key, carBytes, carCid, sourceCid, structure),