# DefenderRelayProvider.send error while verifying signature

**URL:** <https://forum.openzeppelin.com/t/defenderrelayprovider-send-error-while-verifying-signature/12750>\
**Category:** Defender\
**Tags:** defender\
**Created:** [July 19, 2021, 2:45pm UTC](https://forum.openzeppelin.com/t/defenderrelayprovider-send-error-while-verifying-signature/12750 "2021-07-19T14:45:38Z")\
**Posts on this page:** 2\
**Page:** 1

<div class="post-metadata">

**Author:** ![kbhargav5](https://sea2.discourse-cdn.com/flex022/user_avatar/forum.openzeppelin.com/kbhargav5/32/17407_2.png) [@kbhargav5](https://forum.openzeppelin.com/u/kbhargav5)\
**Post date:** [July 19, 2021, 2:45pm UTC](https://forum.openzeppelin.com/t/defenderrelayprovider-send-error-while-verifying-signature/12750/1 "2021-07-19T14:45:38Z")

</div>

Getting the below error while verifying the signature,

2021-07-19T14:13:56.332Z ERROR Invoke Error {"errorType":"Error","errorMessage":"VM execution error.","code":-32015,"data":"Reverted 0x08c379a00000000000000000000000000000000000000000000000000000000000000020000000000000000000000000000000000000000000000000000000000000001d4657443a20756e7265676973746572656420646f6d61696e207365702e000000","stack":["Error: VM execution error."," at DefenderRelayProvider.send (/opt/nodejs/node\_modules/defender-relay-client/lib/ethers/provider.js:58:31)"," at processTicksAndRejections (internal/process/task\_queues.js:97:5)"]}  
END RequestId: 67502e6c-e1f2-446b-9a45-ee7eb9c6e262  
AUTOTASK COMPLETE

#### 🔢 Code to reproduce

```auto
I am using OpenGSN forwarder, signature is different from OpenZeppelin MinimalForwarder, so invoking the verify method based on method signature. Verified input parameters to be valid, but getting this error in defender, Is this error from defender?

```

#### 💻 Environment

---

<div class="post-metadata">

**Author:** ![spalladino](https://sea2.discourse-cdn.com/flex022/user_avatar/forum.openzeppelin.com/spalladino/32/22_2.png) [@spalladino](https://forum.openzeppelin.com/u/spalladino)\
**Post date:** [July 19, 2021, 3:56pm UTC](https://forum.openzeppelin.com/t/defenderrelayprovider-send-error-while-verifying-signature/12750/2 "2021-07-19T15:56:50Z")

</div>

Hey @kbhargav5! The revert data you got from the contract decodes to an error thrown by the OpenGSN forwarder:

```auto
> coder.decode(['string'], '0x0000000000000000000000000000000000000000000000000000000000000020000000000000000000000000000000000000000000000000000000000000001d4657443a20756e7265676973746572656420646f6d61696e207365702e000000')
['FWD: unregistered domain sep.']

```

> <https://github.com/opengsn/gsn/blob/e961c4cc8bc4c79b82a9f63c42124346013170ff/packages/contracts/src/forwarder/Forwarder.sol#L133>

I’d suggest you reach out to the OpenGSN team for help with this one!