Transaction

[Error Code: 1101] error caused by: 1 error occurred:
	* transaction execute failed: [Error Code: 1101] cadence runtime error: Execution failed:
  --> 70b57dd1dfecf6c6a2c71568c0a74db708de82321f0369b36c47290890e6cb3f:10:15
   |
10 |                ref.removeViewPermission(id: tokenId, address :userEthAddress)
   |                ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

error: unexpectedly found nil while forcing an Optional value
   --> ea11c7f74551df98.Certifily:264:23
    |
264 |             let ref = (&self.ownedNFTs[id] as auth &NonFungibleToken.NFT?)!
    |                        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^