report problem on weather underground

After the new update, I did get an API key from weather underground, and set my weather update interval to 1 hour. However, for three consecutive days, I keep receiving emails from wunderground about exceeding my allotted usage, and I am now down to zero "raindrops" according to their message, and probably can no longer use the service.
Below, please find their latest message:
"
Hello,

Your wunderground API key (9689092ccc68ca02) exceeded its allotted usage today by making 25 calls within a minute but the limit is 10.

We used one of your raindrops instead of disabling the key for the remainder of the day. You now have 0 remaining raindrops.

We check usage for 24-hour periods based on U.S. Eastern Time.

The plan you are registered for is Stratus - Developer, granting you 500 calls per day with 10 calls per minute limit. To upgrade your plan go to: http://www.wunderground.com/weather/api/d/9689092ccc68ca02/edit.html

Details: exceededrate: maxrate: 25 (of 10)
Time: Mon, May 16, 2016 14:30 EDT

Thank you,
wunderground.com API Team

This is an automatically generated email; it cannot be replied to. For Documentation review read through:
http://www.wunderground.com/weather/api/d/documentation.html
For Developer questions and forms post in our Community here:
http://www.wunderground.com/weather/api/d/community.html
For Technical Support submit a ticket here:
http://wuhelp.wunderground.com/index.php?_m=tickets&_a=submit&step=1&departmentid=32

--
wunderground.com | 300 Interstate North Parkway, Atlanta, GA 30339
"
Am I doing something wrong? What should I do.

Thanks a lot
Amir M. Amirebrahimi