yoast sitemap submission

After migrating my wordpress blog into my main site https://www.hilinebuilders.com I downloaded the yoast SEO plugin which generates a sitemap for my blog and uploads it very deep into the hierarchy of my site.
I copied the data from that sitemap and pasted it into my pre-existing sitemap in the root folder which I hope is the right thing to do.
But, whenever I submit a new blogpost, the post is automatically submitted to the original,(yoast generated), sitemap, which I am no longer using. Am I able to configure this yoast sitemap to upload to my main sitemap?