V2 API is failing on multiple calls

[NickB331]

We are getting HTTP 400 errors on calls we've been using for years without any issue: 

1. https://api.constantcontact.com/v2/contacts - works with no arguments, but when adding modified_since, there's an 400 error

2.  https://api.constantcontact.com/v2/activities/removefromlists - these are failing with a 400 error also

3. https://api.constantcontact.com/v2/activities/addcontacts - same deal - and there could be more. 

This was working last week - any idea why it stopped? 

[John__B]

Hello NickB331,

Thank you for reaching out to Constant Contact API Developer Support. My team is here to assist outside software developers with questions about building into Constant Contact's API.

It looks like we've already followed up with you directly via email, but I wanted to close the loop here as well. If you haven't received our reply, please let us know via email at webservices@constantcontact.com, and reference case number 31225770.

Please have a look and let us know if you have any other questions!

Regards,