Using version 7.6.5 I've run into an issue where sometimes content doesn't render out on the page at all (and sometimes returns null). This has only come up after a recent upgrade from 7.1. Below is an example of a media type that has image, textbox and richtext properties. I've inserted comments on what's working and what's not... and what's wonky.

@foreach (var bannerItem in Model.Content.HomepageBanner.OfType<HomepageBannerContent>()) {
    foreach (var prop in bannerItem.Properties) {
        // show me all the properties so i know i'm sane
        Print.ToPage(prop.PropertyTypeAlias);
    }
    <div class="slide">
        <div class="slide-text">
            <h2>
                @* textbox content shows perfectly *@
                @bannerItem.ContentTitle
            </h2>

            @* richtext content doesn't show *@
            @bannerItem.ContentText

            @* richtext outputs raw tostring converting html tags to html entities. i.e. literally <p>i am text</p> *@
            @bannerItem.GetPropertyValue("contentText")
        </div>
        <div class="slide-image">
            @* works perfectly *@
            <img src="@bannerItem.BackgroundImage.Url" />
        </div>
    </div>
}

I've been using umbraco for a while now (2 years at least, I forget :) but I can't recall having this many issues since I first started. I can't isolate if it's because of the upgrade (i.e. data not coming up correctly) or I'm just having a series of brain farts. Any help would be appreciated.

Also, if it helps, I am using visual studio 2017, did the upgrade through nuget (with a temporary upgrade to 7.3 from 7.1 to 7.6.5) and have the following setting in my web.config so I can get at my models whilst programming:

<add key="Umbraco.ModelsBuilder.Enable" value="true" />
<add key="Umbraco.ModelsBuilder.EnableApi" value="true" />
<add key="Umbraco.ModelsBuilder.EnableDllModels" value="true" />
<add key="Umbraco.ModelsBuilder.ModelsMode" value="LiveDll" />