C#: Regular Expression for specific pattern string : I want to remove particular string using regex from below: 

Input string:

    {"t":1,"i":"a32dffdd-c99d-4df5-9296-9ae5fb024dc1","p":"At DB Server Time: Wed Sep 27 2017 05:27:18 GMT+0000 (UTC), you sent this message: {\"t\":1,\"i\":\"a32dffdd-c99d-4df5-9296-9ae5fb024dc1\",\"p\":{\"u\":\"/test/delayed\",\"v\":\"GET\",\"h\":{\"X-BH-AgentID\":\"testagent\",\"X-BH-TempToken\":\"testagenttemptoken\"},\"p\":\"\",\"t\":{\"t\":1000}}}"}


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    Remove below string using regular expression: 
    At DB Server Time: Wed Sep 27 2017 05:17:01 GMT+0000 (UTC), you sent this message: 

I want below output:

    {"t":1,"i":"6ca1fca1-c190-40e1-9133-6759bf0c2c95","p":" {\"t\":1,\"i\":\"6ca1fca1-c190-40e1-9133-6759bf0c2c95\",\"p\":{\"u\":\"/test/delayed\",\"v\":\"GET\",\"h\":{\"X-BH-AgentID\":\"testagent\",\"X-BH-TempToken\":\"testagenttemptoken\"},\"p\":\"\",\"t\":{\"t\":1000}}}"}





Thanks in Advanced

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