Hey Darryl,
PJ is on the money here. When you install a new theme you need to add in that code snippet again. It sounds very much like your app thinks the code is already installed, at least in part.
Here's what should fix the app:
STEP 1- Copy the reviews code snippet
This code snippet is what displays the reviews on your website and adds SEO-friendly review scores to your Google search results. Copy the following to your clipboard:
<div id="shopify-product-reviews" data-id="{{product.id}}">{{ product.metafields.spr.reviews }}</div>STEP 2 - Paste the reviews code snippet in your theme
Open your templates/product.liquid file.
In the template, paste the code snippet where you want your reviews to appear (usually beneath the product.description tag) and then save your theme.
That should sync everything together. If not, I'd try one more un-install and re-install. If you get stuck, feel free to post here or shoot us an email at support@shopify.com.
Keep us posted!