I'm also waiting for a payment from the same block...
I contacted Slushpool support a few hours ago and they've already responded with the following ! Hopefully problem will be resolved soon.
Quick response from support !
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We are aware of this issue. Let me please explain what happened and how we are planning to deal with it.
We are doing priority mining which means that we push our own payout transactions into our own infrastructure. The reason is that we want make sure they will be mined as soon as possible.
Sometimes it happens that we mine orphaned block which is valid block but rejected by the network. This is the reason why you see it as Double spend transaction.
If that happens from time to time , we push the same transaction for priority mining once again, however it seems there is an issue with that right now and our priority mining does not work correctly.
We are fixing it right now and you should be able to see it mined in the next 24-48 hours.
Thank you for mining with us, we really appreciate your patience !
Martin
Customer Care
Slush Pool
How did you managed to get in touch with Customer Care?
I have been missing 0.01btc payment from 1st Dec.
(
https://blockchain.info/tx/ddf3d4f14958569215c8e87b675536ac684bedb20aac1f29f73d9af76bfbc6bb )
No reply from slush and i am trying for 5 weeks now...
Its just anoying that i cant find out where is my money.
That transaction went through the same day.