You are obviously using K2 template overrides in your Joomla template which are probably outdated. Load the Protostar template by appending ?template=protostar to the URL in question. If the fields display correctly, it's a template override issue.

For more info on K2 Templating, have a look here: getk2.org/documentation/tutorials/templating-with-k2-and-the-concepts-of-sub-templates

It could also be some third-party plugins that is executed in the K2 item view and it's not compatible with PHP 7. Switching to Protostar would not fix the broken layout, so again it's easy to spot. Search your plugins in that case.