"Failure to send not enough BTC in wallet"

This error usually looks something like:

Error composing send transaction via API: Insufficient BTC at address [Your BTC Address]. (Need approximately 0.00XXXX BTC.) To spend unconfirmed coins, use the flag --unconfirmed. (Unconfirmed coins cannot be spent from multi‐sig addresses.)

• First off, this could simply mean you actually do not have enough BTC in your wallet to pay the fee.

This does not have anything to do with your address being a “multi-sig address”. If you know you do have enough BTC in your account to cover the costs, the reasoning for this error could be many different things.

• The second most common reason this is shown is because you may have some 'unconfirmed' transactions that were sent out from the address, but the Freewallet User Interface has not shown the data yet in the History tab.

Because there can be quite a long time between bitcoin blocks, it's always best to search your address on a BTC block explorer like blockstream.info and a Counterparty block explorer like xchain.io. Before trying to spend the BTC shown in your wallet, take a look to see if any past transactions are still unconfirmed. This error message could simply mean that you have sent out transactions that have not been confirmed, so the balance still shows in your BTC section of Freewallet but a portion of that BTC is not spendable.

• What could also be likely is that you are trying to send the MAX amount of BTC and the fee you are using makes it so you do not have enough btc to send this transaction. The first thing to try here is the change the BTC amount sent and try again.

• Also remember sometimes just closing and re-opening the Freewallet application will update the data Freewallet is pulling from to the latest block data on the blockchain.

• If none of those fixes work, it is more likely this means the amount of BTC on your address is ‘fragmented’ and the total balance you see is actually been split up into many smaller parts which are called UTXO’s (Unspent Transaction Output’s).

This would make more sense as you could well enough have more than enough to cover the BTC fee with your ‘total’ BTC balance, but it is comprised of many many smaller amounts of BTC or UTXO’s that make up that total amount.

You can think of this issue in a different way: You don’t have a $100 bill in your account you have 10,000 pennies in UTXO’s and to cover your costs for the fee you need $1. Freewallet wallet does not let you spend the $1 fee with 100 pennies and will show you this error.

A couple of solutions have been proposed and documented to deal with and fix this issue like here but the simplest one out of all of them is to send more BTC to the address yourself (more than enough to cover the transaction cost) and then send ALL of the BTC in your account to yourself.

In the Bitcoin world this is called “consolidating UTXO’s” and is very common. A good article to review about how UTXO's work and how to deal with them when using Freewallet then check out this Medium Article on the subject.

There is no “consolidating UTXO’s” function natively yet in Freewallet though there are 3rd party wallets that do support this.

If you would like to see this feature supported in Freewallet, join the discussion on the Freewallet github. Every opinion posted there, no matter how small, will help future users and the developer to understand what is wanted in the community regarding Freewallet Functions.

Many community members recommend other wallets to do this process with such as Electrum, but other wallets support this feature too.

Just make sure when you are importing your Private Key for the address you are having this error that you do so with a wallet service you trust.

For more information on what your private key is for this specific address in question and how to view it, review the section titled Displaying the Seed Phrase and Private Key of your Adresses(s).