Transaction

[Error Code: 1101] cadence runtime error Execution failed:
  --> b187b1c5d280af766d1d96955a3ac2c19a974d1184cd29263a097412ad0d210d:13:46
   |
13 |                         self.transferToken <- collectionRef.withdraw(withdrawID: tokenID)
   |                                               ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

error: unexpectedly found nil while forcing an Optional value
   --> 1e3c78c6d580273b.LNVCT:218:63
    |
218 |             let token <- self.ownedNFTs.remove(key: withdrawID)!
    |                                                                ^