Transaction

[Error Code: 1101] cadence runtime error Execution failed:
  --> 55c4bc34d854f5819b410fe2330dc136a66eea736604d6cc9684963982399c29:13:46
   |
13 |                         self.transferToken <- collectionRef.withdraw(withdrawID: tokenID)
   |                                               ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

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