API Error

Hi!

First, thank you for this really nice work, you guys rock!

I am in need of help after 1 year using the plugin:

I was using the API without problems, but from yesterday I started with errors.

Sending the same data will result in Errors Ocurred.

Tried
https://www.mysite.com/?swpm_api_action=create&key=API_KEY&user_name=osvaldo&first_name=Osvaldo&last_name=Janeri&[email protected]

and I got
{“result”:”failure”,”message”:”Missing one of the mandatory fields: first_name, last_name, email”}

* Post or GET, doesnt matter which
* API key is correct, checked twice

How can I debug and correct this over?