Phone field required = Error

[HHC-ST]

I will like to set the phone field as required when the customer check out or make a new address. 

In backoffice I go to Customers -> Addresses -> Enter required fields for this section and select phone. 

But now i can access the cart and checkout process in frontend. It just go to Error 500. RThe rest of the site appears to work fine - I can browse arround in the products, I can also go to my account an enter a new address. 

As soon as I remove phone as an required field again the cart and checkout works perfect again.

I run Prestashop 1.7.2.4

Anyone there can help me?

[bepot]

You need to populate the required fields, in this case "Phone" field, of your already registered customers. For new customers is fine, they will be asked to fill the phone field. With already created users be careful, you need to fill their phone field, otherwise they will not be able to go to checkout.