Failed updating repository: error creating SSH agent: "SSH agent requested but SSH_AUTH_SOCK not-specified"

[ehcpdeveloper]

I added key to key store with ssh key.
When I run a task, this error displayed:
Failed updating repository: error creating SSH agent: "SSH agent requested but SSH_AUTH_SOCK not-specified"

Full error:

11:55:35 AM
Task 2147483646 added to queue
11:55:37 AM
Started: 2147483646
11:55:37 AM
Run TaskRunner with template: task1
11:55:37 AM
Preparing: 2147483646
11:55:37 AM
Cloning Repository root@xxx.net:/gits/xxxx/notes.git
11:55:37 AM
Unable to clone repository: error creating SSH agent: "SSH agent requested but SSH_AUTH_SOCK not-specified"
11:55:37 AM
Failed updating repository: error creating SSH agent: "SSH agent requested but SSH_AUTH_SOCK not-specified"
11:55:37 AM
Running playbook failed: error creating SSH agent: "SSH agent requested but SSH_AUTH_SOCK not-specified"

Anyone has idea?