There are rare cases when a user's balance might be mistakenly increased during a technical maintenance. If a user who received more funds than his hashrate allows withdraws these funds, the account balance becomes negative. There are 2 options for a user to restore the balance:
1. Contact technical support and then send the mistakenly added funds back to the wallet address provided;
2. Do nothing and wait until daily payouts restore the balance to positive values.
There are no other possible cases in which a user's balance might become negative. In a case when the mining costs (the ones covered with the maintenance fee) become higher than the mining revenue, the hardware will be automatically switched off. The hashrate will still remain on users' accounts and will be activated again once the mining becomes profitable.