ConnectMUN stack trace

gistfile1.txt

User is registered for conference
{ conference: 2, user: 8372 }
User is registered for conference
{ conference: 2, user: 8372 }
Handling payment for user d205@gmail.com
Error (E_UNKNOWN) :: Encountered an unexpected error
: ER_BAD_FIELD_ERROR: Unknown column 'NaN' in 'where clause'
    at Query.Sequence._packetToError (/CGYA/Dropbox/CGYA/Firas/Delegate Registation v3/sails/node_modules/sails-mysql/node_modules/mysql/lib/protocol/sequences/Sequence.js:48:14)
    at Query.ErrorPacket (/CGYA/Dropbox/CGYA/Firas/Delegate Registation v3/sails/node_modules/sails-mysql/node_modules/mysql/lib/protocol/sequences/Query.js:83:18)
    at Protocol._parsePacket (/CGYA/Dropbox/CGYA/Firas/Delegate Registation v3/sails/node_modules/sails-mysql/node_modules/mysql/lib/protocol/Protocol.js:274:23)
    at Parser.write (/CGYA/Dropbox/CGYA/Firas/Delegate Registation v3/sails/node_modules/sails-mysql/node_modules/mysql/lib/protocol/Parser.js:77:12)
    at Protocol.write (/CGYA/Dropbox/CGYA/Firas/Delegate Registation v3/sails/node_modules/sails-mysql/node_modules/mysql/lib/protocol/Protocol.js:39:16)
    at Socket.<anonymous> (/CGYA/Dropbox/CGYA/Firas/Delegate Registation v3/sails/node_modules/sails-mysql/node_modules/mysql/lib/Connection.js:96:28)
    at Socket.emit (events.js:107:17)
    at readableAddChunk (_stream_readable.js:163:16)
    at Socket.Readable.push (_stream_readable.js:126:10)
    at TCP.onread (net.js:538:20)
    --------------------
    at Protocol._enqueue (/CGYA/Dropbox/CGYA/Firas/Delegate Registation v3/sails/node_modules/sails-mysql/node_modules/mysql/lib/protocol/Protocol.js:135:48)
    at PoolConnection.query (/CGYA/Dropbox/CGYA/Firas/Delegate Registation v3/sails/node_modules/sails-mysql/node_modules/mysql/lib/Connection.js:201:25)
    at __FIND__ (/CGYA/Dropbox/CGYA/Firas/Delegate Registation v3/sails/node_modules/sails-mysql/lib/adapter.js:834:20)
    at afterwards (/CGYA/Dropbox/CGYA/Firas/Delegate Registation v3/sails/node_modules/sails-mysql/lib/connections/spawn.js:84:5)
    at /CGYA/Dropbox/CGYA/Firas/Delegate Registation v3/sails/node_modules/sails-mysql/lib/connections/spawn.js:40:7
    at Ping.onOperationComplete [as _callback] (/CGYA/Dropbox/CGYA/Firas/Delegate Registation v3/sails/node_modules/sails-mysql/node_modules/mysql/lib/Pool.js:99:5)
    at Ping.Sequence.end (/CGYA/Dropbox/CGYA/Firas/Delegate Registation v3/sails/node_modules/sails-mysql/node_modules/mysql/lib/protocol/sequences/Sequence.js:96:24)
    at Ping.Sequence.OkPacket (/CGYA/Dropbox/CGYA/Firas/Delegate Registation v3/sails/node_modules/sails-mysql/node_modules/mysql/lib/protocol/sequences/Sequence.js:105:8)
    at Protocol._parsePacket (/CGYA/Dropbox/CGYA/Firas/Delegate Registation v3/sails/node_modules/sails-mysql/node_modules/mysql/lib/protocol/Protocol.js:274:23)
    at Parser.write (/CGYA/Dropbox/CGYA/Firas/Delegate Registation v3/sails/node_modules/sails-mysql/node_modules/mysql/lib/protocol/Parser.js:77:12)
    at Protocol.write (/CGYA/Dropbox/CGYA/Firas/Delegate Registation v3/sails/node_modules/sails-mysql/node_modules/mysql/lib/protocol/Protocol.js:39:16)
    at Socket.<anonymous> (/CGYA/Dropbox/CGYA/Firas/Delegate Registation v3/sails/node_modules/sails-mysql/node_modules/mysql/lib/Connection.js:96:28)
    at Socket.emit (events.js:107:17)
    at readableAddChunk (_stream_readable.js:163:16)
    at Socket.Readable.push (_stream_readable.js:126:10)
    at TCP.onread (net.js:538:20)

Details:  Error: ER_BAD_FIELD_ERROR: Unknown column 'NaN' in 'where clause'