Transaction

[Error Code: 1101] error caused by: 1 error occurred:
	* transaction execute failed: [Error Code: 1101] cadence runtime error: Execution failed:
  --> c7b0485097376d1f5edde7708f82e853712a0a04f3101026a2ee451c9d367992:13:46
   |
13 |                         self.transferToken <- collectionRef.withdraw(withdrawID: tokenID)
   |                                               ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

error: unexpectedly found nil while forcing an Optional value
   --> 1e3c78c6d580273b.LNVCT:207:25