Sounds like he got it wrong if he is trying to cheat you... if he really wanted those coins, the other transaction should have had the higher fee!

Unfortunately, none of the transaction accelerators will accept your transaction if it is a double spend. So about your only option would be "Child Pays For Parent"... ie. try and send the unconfirmed output from your transaction to another of your addresses with a MASSIVE fee, such that the average fee for both transactions would be like 300+ sats/byte.

I hope you did not send this guy any money or products or provide any services...You should NEVER do that until the transaction gets at least 1 confirmation.


As for the CPFP... it would go something like this:

- If I'm reading your message right... you were supposed to get 0.1105434 BTC to 1Pngc9UQUrhCFJFnYhvY7iE3N3FyrAsWh5 in the 71a61... TX? (this is your address right?)
- What you'd want to do, is send that output from 1Pngc9UQUrhCFJFnYhvY7iE3N3FyrAsWh5 to another address in your wallet... and use a fee of ~450 sats/byte... so the combined average fee across both "your" transactions was greater than the current recommended fees (~300 sats/byte)

For example, if you sent 0.1096794 from 1Pngc9UQUrhCFJFnYhvY7iE3N3FyrAsWh5 to another address in your wallet and made sure the fee was 0.00086400 btc (0.1096794 + 0.00086400 = 0.1105434)... then you'd have the overall fees as:

Size = 226 bytes (trans you want to push) + 192 (new trans) = 418 bytes
Fees = 0.00047119 BTC + 0.00086400 btc = 0.00133519 btc = 133519 sats

Overall fee = 133519 sats / 418 bytes = ~319 sats/byte... which is a "decent" fee at the moment... so the miners would prioritise both of them into a block


NOTE: you would want to do this AFTER the bbf69880c3464b7c6f316738b0f496580186ff051ebf25396fc6efc7f128f83e transaction gets a confirmation. (Try pushing it using the ViaBTC TX Accelerator)

If I was you, i'd do the following things:
I'd try to get bbf69880c3464b7c6f316738b0f496580186ff051ebf25396fc6efc7f128f83e into a block, you can use my tool to look at your options:
https://www.mocacinno.com/feecheck.php?txid=bbf69880c3464b7c6f316738b0f496580186ff051ebf25396fc6efc7f128f83e . I think viabtc is the best option for you now.. I'd defenately wouldn't pay anybody to get this transaction into a block, since this is only the transaction whose output was used as an input for your transaction

Then, i'd hope your transaction got into a block before the double spending one did...

IF bbf69880c3464b7c6f316738b0f496580186ff051ebf25396fc6efc7f128f83e makes it into a block, and the sender doesn't decide to tripple spend the input for your unconfirmed transaction with a much higher fee, the odds are pretty good that your transaction will be confirmed, and not the double spending one... Why? Because it was broadcasted first, so most nodes will have accepted it, while the other one was broadcasted hours later, so some nodes might have rejected it AND the fee is much higher, so it gives the miners much more incentive to put your tx into the block their working on compared to putting the double spend transaction into a block...

It would also be a good idear to contact the sender once your transaction gets confirmed, and notify him of the problem... If the double spending transaction was also generated to pay somebody, this other person's transaction will be cancelled as soon as yours makes it into a block...

If this is your transaction, the odds are pretty big that it will indeed have a bigger chance of getting into a transaction as the competing transaction... However, both transactions use the same UNCONFIRMED input

https://blockchain.info/tx/bbf69880c3464b7c6f316738b0f496580186ff051ebf25396fc6efc7f128f83e

This means that neither you, nor the double spent can get into a block before bbf69880c3464b7c6f316738b0f496580186ff051ebf25396fc6efc7f128f83e gets into a block, and the sender seems to know a way to double spend the same inputs and broadcast them to the network, this means there is no way of telling if he will double spend the inputs for bbf69880c3464b7c6f316738b0f496580186ff051ebf25396fc6efc7f128f83e using a higher fee, thus lowering the chance bbf69880c3464b7c6f316738b0f496580186ff051ebf25396fc6efc7f128f83e will ever make it into a block...

Could you post the transaction id?
If your transaction has a higher fee, and it has the same inputs and roughly the same size, the odds are good that your transaction will end up in a block, but certainly not 100%

Beschwere ich beim Versender der Coins.

Es gibt ca. zwei Hand voll Mining-Pools mit nennenswerten Kapazitäten auf der ganzen Welt.
Und die werden gerade auf jemanden Warten, der "Blödsinn" mit seiner Überweisung macht und sich lange Geschichten anhören wollen, wie es zu einem Doublespend gekommen ist und warum eine der beiden transaktionen wichtiger ist als die andere.
...um am Ende $0,87 Gebühren für die TX zu ergattern. Hier im Forum ist kein User aus eigener Kraft in der Lage (in absehbarer Zeit) einen Block zu finden und die großen Miner beschäftigen sich nicht mit Einzelschicksalen von 0,x Bitcoins.

Nicht nur die gleiche AbsenderADRESSE, sondern exakt die selben INPUTs (Coins). Das ist ja das Problem.

Der Absender versucht (absichtlich oder nicht) Geld doppelt auszugeben.

Kennst Du denn einen von den Schinesen persönlich? 
Ansonsten könntest Du ja noch heute mit dem Solomining beginnen und die Tx selbst bestätigen...frag mich aber nicht wie das auszuwählen geht! 

Das Alter einer Transaktion interessiert den Miner nicht, nur die Fee 


Was wiederum mit dem Double-Spend zu tun haben wird.

Deine ist die mit der höheren Fee? Dann ist es diese: 71a61f01d4e436b4bbb50847d9d6b7802dc6308a4bcd3a1a3ab6bbac55eca7d8
https://blockchain.info/de/tx/71a61f01d4e436b4bbb50847d9d6b7802dc6308a4bcd3a1a3ab6bbac55eca7d8

mach dir nichts daraus. Meine erste Transaktion hatte ich mit so wenig fee eingestellt (weil ich es einfach nicht wusste) dass es geschlagene 48h gedauert hatte bis die Transaktion bestätigt war.

Also ruhig bleiben und tee trinken

ja genau, das ist ein Doublespend. Die Transaktion 1adfaea5fb2b5976cb699d070dbc44384f10857d6cdbbc347f64bf54ff19ac56 konkurriert um die selben Coins.

Das hat der Sender verbockt und die Miner tun sich nun schwer die TX aufzunehmen.