Who I have the same questioned this topic

This is not the experience we want you to have with our store locations or t hat awesome new phone you have Rowdyjane57. I'm sorry you were unable to replace your phone. I was able to locate customers who were also concerned about the split screen. We uplifted this to the manufacture and was advised this how the phone was designed. There is no way to disable the split screen compleely. I'm sorry for the inconvenience.

We received information advising there are steps to disable Split view for Messages in landscape orientation (Messages > More > Settings > More settings > Split view or Email > More > Settings > Split view mode)

KinquanaH_VZW
Follow us on Twitter @VZWSupport
If my response answered your question please click the ?Correct Answer? button under my response. This ensures others can benefit from our conversation. Thanks in advance for your help with this!