"Taker's trade price is too far away from our calculated price based on the market price."

I am selling some BTC for GBP and just got this error message when a taker accepted the trade. In full, it says:

An error occurred when someone tried to take one of your offers:
An error occurred at task: MakerProcessPayDepositRequest
Taker’s trade price is too far away from our calculated price based on the market price.

[I adjusted the numbers a bit just for privacy]

This was then followed by another error popup with the same content except for an additional line at the end:

Exception: java.lang.IllegalArgumentException

After closing these windows, I seem to be able to proceed with the trade as normal. I can see that the buyer has already sent me the money and I have the “Confirm payment receipt” button. However the amount he sent me does seem to be roughly £40 less than what I would have expected. Could this be some kind of elaborate attack to weasel out some extra money from me?

It seems from checking bitcoinaverage.com and some other exchange prices that the BTC price really never was as low as the “tradePrice” appears. But I’m not sure how to confirm this properly. I don’t know what price index Bisq uses.

So is this a red flag? Should I open a dispute or should I just go ahead with the trade? Thanks.

Oh, actually I just checked bitcoinaverage.com again, and it looks like the price really was that low about 18 hours ago–which is after I published my trade. So this does look it’s probably legitimate.

However the two error message still worry me. Should they? Or are they likely to pop up just during periods of high volatility?

Lastly can anyone tell me where to look for a price record that Bisq refers to? Thanks a lot.

The % based price used the BitcoinAverage price and is calculated on both traders side independently and the maker verifies it in the trade process that the difference is inside a small tolerance window. If the price is too far away the trade fails. We have 3 price provider nodes which get the price from BitcoinAverage and it can be that both traders are connected to 2 different ones and in times of very high volatility it might be that the nodes deliver different prices which exceeds the tolerance. So that case is legit.
What is strange that the price is so much different. If there have been a volatility spike at take offer time it is explainable as the nodes request each 90 sec.
What is strange that the trade did not fail. Seems to be a bug.
That the trade amount is different is a result of the different price the taker had.

You can open a dispute, pay back the Pound and tell the arbitrator about what I explained here. So that trade gets cancelled. If you are OK with the price the taker had you also can just continue and the trade completes normally.

I will check why that does not lead to a failed trade. Can you send me your log file (account/backup - button to open it). I will PM u my email. I will be traveling the next days so will take a while until I respond.

(Hmm, perhaps I should have quit the trade as you suggested, since it seems I am now about £260 down!)

After my previous post when I discovered that the price could really have been as low as the tradePrice emerged as, I decided to go ahead with the trade anyway. However I have also now discovered that the “reason for payment” code has not appeared anywhere on my bank statement. Instead, the buyer’s name appears where I would expect the code to be. So it looks like a mistake of his. Not sure if this is grounds to get out of the trade, but I’m going through this with the arbitrator now.

I’ll send you the logs once the trade has resolved, unless you’d rather I send them now?

Yes, the dispute is probably the best way to go here.