 [eth1] System.Exception: eth_sendTransaction returned error: unknown account code -32000
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![image](https://user-images.githubusercontent.com/29943599/148653001-8c43873d-c990-4036-a078-92542d8e6850.png)


how can I solve this problem, I guess the problem is in the config.json -> "paymentProcessing" block, I didn't set the payment private_key, Can u tell me how to set my private_key into the config.json, then miningcore can use PPLNS to send ETH rewards to the miner address? 
If I can't set private key in config.json, Should I must create a local eth account by using "geth account new" command, and then when I start geth, I also has to set the password into the geth command? Finally, how to set this account password in mingingcore config.json ?