Quotas

Service quotas, also referred to as limits, are the maximum number of service resources or operations for your AWS account.

Sufficient AWS Lambda concurrent executions limit

Use AWS Service Quotas in your AWS console to verify your AWS Lambda concurrent executions. The Applied quota value in your account should be greater or equal to the AWS default quota value (which is 1000). If the Applied quota value is less than 1000, select the Request quota increase button to request an increase to this value to at least 1000 before deploying the solution. For more information, refer to the AWS Lambda Developer Guide..