FiveTran getting error "Plan exceeded"

Hello,

We are moving Front messages to our data warehouse using FiveTran, we are experiencing error while fetching the data via API. I initially contacted FiveTran, but they told me the error is coming from Front side and contact you guys. 

Below is the error message. 

{
"_error": {
"message": "Plan exceeded.",
"status": 403,
"title": "Forbidden",
"type": "resource_unavailable"
}
}