Transaction

[Error Code: 1101] error caused by: 1 error occurred:
	* transaction invocation failed when executing transaction: [Error Code: 1101] cadence runtime error: Execution failed:
  --> f4c549e88594bf70abfa1a624b3bcb566ac6c538c6ac52535862d3f90945dfd6:12:46
   |
12 |                         self.transferToken <- collectionRef.withdraw(withdrawID: tokenID)
   |                                               ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

error: unexpectedly found nil while forcing an Optional value
  --> 8f3e345219de6fed.NFL:69:25
   |
69 |             let token <- self.ownedNFTs.remove(key: withdrawID)!
   |                          ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^