AWS Lambda error GraphQlError: Adapter is not a function when attempting to run mutations to AppSync endpoint

I am running a lambda inside my AWS account that is attempting to run mutations against an AppSync instance in the same account which is authenticated via AWS_IAM. I have created a Role that my lambda assumes which has access to my mutations with the following document:

{
    "Action": [
        "appsync:GraphQL",
        "sts:AssumeRole"
    ],
    "Resource": "arn:aws:appsync:us-west-2:<MyAWSAccountId>:apis/<MyAppSyncAPiId>/types/Mutation/fields/*",
    "Effect": "Allow"
},

However, I receive the following error below:

Error

{
  data: {},
  errors: [
    GraphQLError: adapter is not a function
        at APIClass.<anonymous> (/var/task/node_modules/@aws-amplify/api/dist/aws-amplify-api.js:4627:24)
        at step (/var/task/node_modules/@aws-amplify/api/dist/aws-amplify-api.js:3800:19)
        at Object.throw (/var/task/node_modules/@aws-amplify/api/dist/aws-amplify-api.js:3730:14)
        at rejected (/var/task/node_modules/@aws-amplify/api/dist/aws-     amplify-api.js:3692:32)
        at runNextTicks (internal/process/task_queues.js:62:5)
        at processImmediate (internal/timers.js:429:9)
        at process.topLevelDomainCallback (domain.js:137:15)
  ]
}

The lambda auth code works when I am running in my test account, and I have verified that the permissions are same between both test account and this account. I have also verified that the account id and api Id are correct and schemas match.

I am a little lost as to what this error signifies since I am using the same libraries in test and production. Is there anything else that could be mismatched in accounts that can result in this error?

Solution

After digging online found: https://github.com/aws-amplify/amplify-js/issues/4311#issuecomment-562789876

Using "@aws-amplify/api": "^2.2.0", caused mismatch error. I ended up downgrading to: "@aws-amplify/api": "^2.1.0", as versions greater then > 2.2.0 caused missing identity pool errors.

Final set of dependencies in my package.json:

"@aws-amplify/api": "^2.1.0",
"aws-amplify": "^2.1.0",
"aws-sdk": "^2.6.x",
"aws-appsync": "^2.0.2",
"amazon-cognito-identity-js": "^3.0.x",