serverless-s3-sync Crash! callback called twice

eg.

 s3Sync:
    - bucketName: bucket1
      bucketPrefix: prefix1
      localDir: dir1

    - bucketName: bucket1
      bucketPrefix: prefix2
      localDir: dir2

    - bucketName: bucket1
      bucketPrefix: prefix3
      localDir: dir3

`S3 Sync: Syncing directories and S3 prefixes... ..../usr/local/lib/node_modules/serverless/node_modules/aws-sdk/lib/request.js:31 throw err; ^

Error: callback called twice at onCb (/Users/xxxxxx/xxxxxxxxxxx/node_modules/pend/index.js:36:23) at Response. (/Users/xxxxxx/xxxxxxxxxxx/node_modules/@monolambda/s3/lib/index.js:406:9) at Request. (/usr/local/lib/node_modules/serverless/node_modules/aws-sdk/lib/request.js:364:18) at Request.callListeners (/usr/local/lib/node_modules/serverless/node_modules/aws-sdk/lib/sequential_executor.js:105:20) at Request.emit (/usr/local/lib/node_modules/serverless/node_modules/aws-sdk/lib/sequential_executor.js:77:10) at Request.emit (/usr/local/lib/node_modules/serverless/node_modules/aws-sdk/lib/request.js:683:14) at Request.transition (/usr/local/lib/node_modules/serverless/node_modules/aws-sdk/lib/request.js:22:10) at AcceptorStateMachine.runTo (/usr/local/lib/node_modules/serverless/node_modules/aws-sdk/lib/state_machine.js:14:12) at /usr/local/lib/node_modules/serverless/node_modules/aws-sdk/lib/state_machine.js:26:10 at Request. (/usr/local/lib/node_modules/serverless/node_modules/aws-sdk/lib/request.js:38:9) at Request. (/usr/local/lib/node_modules/serverless/node_modules/aws-sdk/lib/request.js:685:12) at Request.callListeners (/usr/local/lib/node_modules/serverless/node_modules/aws-sdk/lib/sequential_executor.js:115:18) at Request.emit (/usr/local/lib/node_modules/serverless/node_modules/aws-sdk/lib/sequential_executor.js:77:10) at Request.emit (/usr/local/lib/node_modules/serverless/node_modules/aws-sdk/lib/request.js:683:14) at Request.transition (/usr/local/lib/node_modules/serverless/node_modules/aws-sdk/lib/request.js:22:10) at AcceptorStateMachine.runTo (/usr/local/lib/node_modules/serverless/node_modules/aws-sdk/lib/state_machine.js:14:12) at /usr/local/lib/node_modules/serverless/node_modules/aws-sdk/lib/state_machine.js:26:10 at Request. (/usr/local/lib/node_modules/serverless/node_modules/aws-sdk/lib/request.js:38:9) at Request. (/usr/local/lib/node_modules/serverless/node_modules/aws-sdk/lib/request.js:685:12) at Request.callListeners (/usr/local/lib/node_modules/serverless/node_modules/aws-sdk/lib/sequential_executor.js:115:18) at callNextListener (/usr/local/lib/node_modules/serverless/node_modules/aws-sdk/lib/sequential_executor.js:95:12) at Request.RESET_RETRY_STATE (/usr/local/lib/node_modules/serverless/node_modules/aws-sdk/lib/event_listeners.js:442:9) at Request.callListeners (/usr/local/lib/node_modules/serverless/node_modules/aws-sdk/lib/sequential_executor.js:101:18) at Request.emit (/usr/local/lib/node_modules/serverless/node_modules/aws-sdk/lib/sequential_executor.js:77:10) at Request.emit (/usr/local/lib/node_modules/serverless/node_modules/aws-sdk/lib/request.js:683:14) at Request.transition (/usr/local/lib/node_modules/serverless/node_modules/aws-sdk/lib/request.js:22:10) at AcceptorStateMachine.runTo (/usr/local/lib/node_modules/serverless/node_modules/aws-sdk/lib/state_machine.js:14:12) at /usr/local/lib/node_modules/serverless/node_modules/aws-sdk/lib/state_machine.js:26:10 at Request. (/usr/local/lib/node_modules/serverless/node_modules/aws-sdk/lib/request.js:38:9) at Request. (/usr/local/lib/node_modules/serverless/node_modules/aws-sdk/lib/request.js:685:12) at Request.callListeners (/usr/local/lib/node_modules/serverless/node_modules/aws-sdk/lib/sequential_executor.js:115:18) at Request.emit (/usr/local/lib/node_modules/serverless/node_modules/aws-sdk/lib/sequential_executor.js:77:10) at Request.emit (/usr/local/lib/node_modules/serverless/node_modules/aws-sdk/lib/request.js:683:14) at Request.transition (/usr/local/lib/node_modules/serverless/node_modules/aws-sdk/lib/request.js:22:10) at AcceptorStateMachine.runTo (/usr/local/lib/node_modules/serverless/node_modules/aws-sdk/lib/state_machine.js:14:12) at /usr/local/lib/node_modules/serverless/node_modules/aws-sdk/lib/state_machine.js:26:10 at Request. (/usr/local/lib/node_modules/serverless/node_modules/aws-sdk/lib/request.js:38:9) at Request. (/usr/local/lib/node_modules/serverless/node_modules/aws-sdk/lib/request.js:685:12) at Request.callListeners (/usr/local/lib/node_modules/serverless/node_modules/aws-sdk/lib/sequential_executor.js:115:18) at callNextListener (/usr/local/lib/node_modules/serverless/node_modules/aws-sdk/lib/sequential_executor.js:95:12) at Request. (/usr/local/lib/node_modules/serverless/node_modules/aws-sdk/lib/event_listeners.js:296:11) at Request. (/usr/local/lib/node_modules/serverless/node_modules/aws-sdk/lib/request.js:685:12) at Request.callListeners (/usr/local/lib/node_modules/serverless/node_modules/aws-sdk/lib/sequential_executor.js:115:18) at Request.emit (/usr/local/lib/node_modules/serverless/node_modules/aws-sdk/lib/sequential_executor.js:77:10) at Request.emit (/usr/local/lib/node_modules/serverless/node_modules/aws-sdk/lib/request.js:683:14) at error (/usr/local/lib/node_modules/serverless/node_modules/aws-sdk/lib/event_listeners.js:295:22) at ClientRequest. (/usr/local/lib/node_modules/serverless/node_modules/aws-sdk/lib/http/node.js:83:7) at Object.onceWrapper (events.js:313:30) at emitNone (events.js:106:13) at ClientRequest.emit (events.js:208:7) at TLSSocket.emitTimeout (_http_client.js:708:34) at Object.onceWrapper (events.js:313:30) at emitNone (events.js:106:13) at TLSSocket.emit (events.js:208:7) at TLSSocket.Socket._onTimeout (net.js:407:8) at ontimeout (timers.js:475:11) at tryOnTimeout (timers.js:310:5) at Timer.listOnTimeout (timers.js:270:5)`