Bug report, issue in Polymarket crypto 5-minute markets.

Bug report

I am reporting an intermittent issue in Polymarket crypto 5-minute markets.

The problem is that sometimes the UI shows that my position was sold before the market resolved, but the proceeds from that sale do not appear to be credited correctly to my account.

What I mean exactly:

• I buy a position in a 5-minute crypto market.

• Before the market resolves, I place a sell order using FOK (Fill-Or-Kill).

• Since FOK orders should either be fully filled immediately or not executed at all, I expect that if the UI shows a sale, it means the position was fully sold.

• However, in some cases, even though the UI shows the position as sold, the account balance and final result do not match that sale.

As you can see in the attached screenshot, the market history clearly shows:

• Bought 24 Down at 92¢ ($22.37)

• Sold 23 Down at 46¢ ($10.45)

So from the UI side, it clearly appears that the sell went through.

What should happen:

If a sell is shown in the UI after using an FOK order, then the sold amount should already be credited to my account, and only any unsold remainder should still be exposed to the final market result.

What seems to be happening instead:

In some cases, the UI shows the position as sold, but if the market later resolves against the side I originally held, the final result looks as if I never sold at all and I lose the full position.

So from the user side, it looks like this:

• the UI says the position was sold,

• the screenshot/history confirms that it was shown as sold,

• but the credited balance does not reflect that correctly,

• and later the final outcome behaves as if the earlier sale did not count.

This is not happening every time.

Sometimes early sells work normally and I receive only the amount I sold for, which is expected.

But other times, the behavior is inconsistent and makes it look like there may be one of the following issues:

• the UI is showing a completed sale even though the FOK order was not actually filled,

• there is a mismatch between order execution and UI display,

• the sell was recorded in history but not credited correctly in account balance,

• or there is a settlement, accounting, or display bug.

I also noticed related confusing behavior in some cases where:

• a bought position appeared in my portfolio,

• but the history / redemption side did not display clearly,

• or the position later disappeared in a way that did not match what I expected after an early sell.

This issue does not appear to be limited to one asset only. At first I thought it was specific to ETH 5-minute markets, but after checking more cases, it seems it may also affect other crypto 5-minute markets.

Please review for my wallet:

1. whether the sells shown in the UI, especially FOK orders, were actually fully executed,

2. whether there is any case where an order is shown as sold in history but the proceeds were not actually credited,

3. whether any portion remained open into resolution,

4. whether the history display is incorrectly marking sells as completed,

5. and whether there is an intermittent UI, settlement, or accounting bug.

Wallet address:
0x8102dEF752AD31eBbDCc8f849Ff92ee4845d53f2

Example markets:

• eth-updown-5m-1774207800

• eth-updown-5m-1774213500

I am attaching screenshots as evidence. As you can see in the picture, the market history itself shows the buy and the sell, which is why the later account result is so confusing.

I can provide screenshots, timestamps, and any additional details immediately.

Short version

I am using FOK (Fill-Or-Kill) sell orders, so if the UI shows a position as sold, it should mean it was fully filled. As you can see in the attached screenshot, the history shows “Bought 24 Down at 92¢ ($22.37)” and “Sold 23 Down at 46¢ ($10.45).” However, in some crypto 5-minute markets, even though the UI shows the position as sold, the proceeds are not credited correctly, and if the market later resolves against my side, it looks as if I never sold and I lose the full position. This does not happen every time. Please check whether FOK orders are being incorrectly shown as sold in the UI, or whether there is a settlement/accounting/display bug.