What is the response you are getting when they are dropped? If you are getting a 429 - To Many Requests, then that is due to the throttling we must enable on the API Endpoints.
Our API-Tokens are limited to 100 requests per second, with a burst of 200 requests. What this means, if you haven't made any prior requests in the previous 2 seconds, you can make 200 requests. Then you will be able to continuously make 100 requests per second until you reach the limit of your key, which is 500,000 requests per month for each production key.
If you are getting a different error, please let us know. BTW - we use AWS API Gateway for these services so any information found about API Gateway will apply to these endpoints.
Thanks,