Im using a plugion UNI CPO builder to make a single product, and i have activated on my single product related products.
The price of related producs is updated with the price of my main single product.
Support of UNI CPO tell me this: It is because your theme uses same markup for the main product’s price tag as well as for related. Update CSS selector to point only to the main tag or change markup in your theme.
Please follow up with the plugin support and show them that the same issue exists in the a default theme so it’s likely an issue on their end and not the theme.