Editors' note, May 12 This post has been updated with comment from Amazon.

Amazon expanded Echo's feature set this week with a seemingly benign Alexa calling feature. Thanks to an update to the Alexa app that came down this week, you can now use your Echo to call other Echo users on your contact list, hands-free.

It sounds very convenient, but there's a catch. There is no way to block people from your contact list from calling you. It sounds improbable, but Amazon has included no way to block individual contacts in the app update. It also has no way within the app to disable the calling feature wholesale once you turn it on. Fortunately there's a solution, but it's rather clumsy.

Now playing: Watch this: Alexa introduces voice calling and messaging

How does Alexa handle your contacts in the first place?

Through the Alexa app on your phone, you must first enable Alexa calling, then grant Amazon permission to scan your phone's contact list. Once it completes that scan, Amazon builds an Alexa-specific contact list based on your contacts who have also enabled the Alexa calling feature.

That means anyone on your phone's contact list -- your plumber, your dentist, your boss or an ex -- can call your Echo directly, even if you've blocked their calling privileges on your phone's contacts.

Elise Oras, a marketing and events manager in Raleigh, North Carolina, first documented this issue and Amazon's clumsy solution in a Medium post earlier today. Here's what you have to do.

Head over to Amazon's contact page

Enlarge Image Rich Brown/CNET

For now, your only option to protect your Echo from unwanted calls is to disable the calling feature completely. To do that, you need to call Amazon directly.

To get the right department at Amazon, head to the Amazon contact page and be sure to log in to your account. From there you need to navigate through a set of basic questions to filter down to this specific issue. Select "Amazon Devices and Kindle Apps" at the top of the page, select your Echo, then select Echo Devices from the second part of the questionnaire. For "Issue details" there is no specific "Alexa calling" option, so go with "Something Else."

In section 3, choose the phone option, which will take you to a page where you can enter a phone number by which Amazon customer support can reach you. I received a callback about 10 seconds after I entered my number.

What happens when you call?

Once you're on the phone, you'll be prompted to press "1" to prove you're a real human and not a bot. I called at around 5:10 PM ET on a Friday, and had to hold for about a minute (and was prompted to push "1" again) before a human picked up. Your hold time may vary depending on the time of your call.

The service rep who eventually answered the phone was friendly, even though she seemed surprised by my request to cancel Alexa calling. She asked me to wait while she looked up the solution, and at first thought I might need to submit a form. She put me on hold for about a minute, and then got back on to inform me that she did indeed have the ability to disable Alexa calling from her workstation. She gave me no pushback on my request, which was a pleasant surprise.

Once she disabled calling on her end, she informed me that I would have to log out of the Alexa app on my phone and log back in to complete the disabling process. I own only one Echo, an Echo Dot, but she told me that if I had multiple Echo units, the process would be the same.

You need to call again if you want to turn the service back on (once you've deleted any unwanted contacts from your phone's contact list).

This scorched-earth approach to contact management is obviously a poor substitute for a contact-by-contact approach. An Amazon representative informed me a call-blocking feature is in the works, and it will be released "in the coming weeks."