Binance, the world’s largest crypto exchange by trading volume, has temporarily suspended withdrawals of DOGE following an upgrade, the company said Thursday.

“We discovered a minor issue with DOGE network withdrawals on Binance after carrying out a version update on 2021-11-10,” Binance said in a post on Thursday morning without specifying what the “minor issue” was. “As a result, we have temporarily suspended DOGE network withdrawals until this issue is resolved. Binance is actively working with the DOGE project team to resolve the issue.”

But the upgrade appears to have created significant problems for some of Binance’s users. Those users claim that the crypto exchange first initiated the withdrawal of dogecoin without their consent, and is now asking the users to return the dogecoin that they don’t have in their Binance accounts.

Screenshots shared with CoinDesk by several Binance users show that Binance asked them to return DOGE to the exchange, or else their withdrawal function on the exchange would remain deactivated. But the affected users said they didn’t even have any DOGE in their Binance accounts to return.

In a tweet thread on Thursday by a Twitter account representing dogecoin developers, the developers explained that the initial withdrawal transactions appear to have been follow-up attempts to carry out requested transactions from years ago that were “stuck” because of “insufficient fees.”

The Dogecoin network upgrade initiated a few days ago appears to have triggered those old transactions, according to the tweet thread. On the upgrade’s GitHub page, it says the upgrade made final “a new minimum fee recommendation” for all participants on the network; the developers therefore believe that the transactions that got stuck appear to have been retried, even when the users no longer own the coins.

The Dogecoin developers claimed that they tried to work with Binance when the exchange first reached out over a year ago on the “stuck transactions,” but they “were not notified as to whether or not [Binance] followed” their instructions to fix the problem.

Binance didn’t immediately respond to requests for more information about the issue.