Let me start out by saying I've inherited this project and am VERY new to the whole constant contact thing.
We are trying to Post a large amout of data (20352 lines) and when doing so we get the "Bad Request" error. This only seem to happen when we do lage amounts. It gets the error while getting the response.
I'm not sure what else you need to help so please let me know what info you might need.
Thanks for reaching out for help. If you haven't found it already, our developer portal is a great place to learn about our API platform. If you can let me know:
I can start to help you figure out what's happening.
I'm going to assume (dangerous, I know) that you're using the Bulk Activity Import Contacts endpoint. You import a maximum of 20k contacts per call, or a payload not exceeding 4 MB. Check out the Limitations section on the link to documentation I included.
The issue you are running into is that our URL Encoded bulk import endpoint also has a data limit at 1.9MB. Here is a quote from the documentation for this endpoint:
Currently, we can add up to 1.9MB of encoded data in the string (about 2 million characters). Larger data strings should be broken up and added in batches.
The best method to resolve this is to place a limit on the number of contacts in a single batch before you split it into two parts and upload them separately.
If you have any questions, please let me know!