Reload value after executing a plugin to delete message.

In capturing opportunities is the subgrid quote.

I create a plugin that runs when a new quote is created the opportunity that adds the value of the contributions of that opportunity and I assign that value to a field that I believe. As more quote created my plugin updates the total value of contributions.
My problem is when I created a plugin that runs when a quote of subgrid is eliminated. when you are running the plugin that runs correctly on the screen but does not update the value of the custom field. This case is not presented with the plugin to create or update these if the value updated immediately.