Transaction

[Error Code: 1101] cadence runtime error Execution failed:
  --> 1c06317deeccec2b0d23109fcfa065633b68248e21219b305911c4708c4359bf:13:46
   |
13 |                         self.transferToken <- collectionRef.withdraw(withdrawID: tokenID)
   |                                               ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

error: unexpectedly found nil while forcing an Optional value
   --> 1e3c78c6d580273b.LNVCT:218:63