Token(CannotCreate) error on transferring asset to PalletId account

Question

I'm new to Substrate and I'm creating a pallet in which the user can create contests by depositing a certain amount of assets. My idea is to send that amount to the PalletId account, but I'm having an error "Err(Token(CannotCreate))" when testing, and it's happening in the following function:

T::Assets::transfer(
  prize_token_id,
  &who,
  &Self::account_id(),
  prize_token_amount,
  false
)?;

I didn't find it when I tried to see if anyone had something like this. I know the error is related to providers and consumers, but I couldn't relate it to my problem.

What could be happening to throw this error?

EDITED:

The repo is here: https://github.com/pablolteixeira/constests-unit-network/blob/main/substrate-node-unitchain/pallets/contests/src/lib.rs

On line 240, it's possible to find the "transfer" function that is panicking.

cargo test -p pallet-contests is sufficient to see the error happening.

Answer 1

Without more context, this could be your issue:

The tokens trait has an DepositConsequence enum which one of its variants is CannotCreate which means:

Deposit cannot happen since the account cannot be created (usually because it’s a consumer and there exists no provider reference).