Transaction signing issue

[shamtroon]

Hello team,
I am trying to sign a transaction and broadcast it, but I didn't find any method to sign a transaction using this sdk. Also I didn't find any example or sample code for it. Although I did some R&D and create a method to sign a transaction but I am facing this issue while sending the transaction

[Error Code: 1006] invalid proposal key: public key 0 on account eabdfe827c7db887 does not have a valid signature: [Error Code: 1009] invalid envelope key: public key 0 on account eabdfe827c7db887 does not have a valid signature: signature is not valid

Kindly help me to solve this issue