Question: During checkout, I get a long list of "€0" for my shipping methods:
[![shipping methods](https://i.stack.imgur.com/dTFec.png)](https://i.stack.imgur.com/dTFec.png)

However, in the admin panel, I enabled only the fixed shipment option and set it to €5 per order.

I'm using Magento 2.0.8. 

Nothing happens when I click the "next" button to proceed to payment.

I have no JS errors, neither I find errors in var/reports.

Answer: 
You may check our answer to your question [here](https://community.magento.com/t5/Technical-Issues/Checkout-Summary-shows-undefined-undefined-shipping-before/m-p/29722#M460): 

I'll copy-page the massage just in a case:

> 
> If after entering address details your checkout looks somewhat like
>  this:
> 
> 
> [![enter image description here](https://i.stack.imgur.com/c8hgR.png)](https://i.stack.imgur.com/c8hgR.png)
> 
> 
> ... most likely the reason why the issue occurs is because your
>  service doesn't provide the correct response to the
>  estimate-shipping-methods query.
> 
> 
> You can check what the server response in the browser console:
> 
> 
> [![enter image description here](https://i.stack.imgur.com/GQqFy.png)](https://i.stack.imgur.com/GQqFy.png)
> 
> 
> The inability of Magento 2 to process cases with invalid JSON in a
>  server response makes the script put a high load on the browser (it
>  just gets in a loop). Plus, the script creates a big amount of
>  "s\_method\_undefined\_undefined" methods ("undefined" means that when
>  sending a query, no response was received, since the object is empty).
> 
> 
> In most cases, the issue was caused by the absence of these php.ini
>  settings:
> 
> 
> 
> ```
> date.timezone = America/New_York
> always_populate_raw_post_data = -1
> 
> ```
> 
> Right after you add them, the checkout should start working as
>  expected.
> 
> 
> [![enter image description here](https://i.stack.imgur.com/2VXnO.png)](https://i.stack.imgur.com/2VXnO.png)
> 
> 
> Most likely, a similar issue can occur because of other missing php
>  settings -- they can trigger errors when executing the code.
> 
> 
> Also, most likely, disabling error display (magento deploy:mode:set
>  production) will let you avoid such behaviour at the checkout step.
> 
> 
>
proposal : check for promotions for this error.

Magento ver. 2.2.5 admin panel.
"Marketing > Promotions > Cart Price Rulse"

you can get the error if the cargo is to be in cart price rules.