Incompatible with Wistia video sitemap

The version number of WordPress 3.9.1
and the plugin 4.0.6
The URL to your blog https://www.annuity-lead.com
Other plugins: https://screencast.com/t/yEU22pTNV

Wistia gives me these instructions for adding their sitemap to robots.txt: https://screencast.com/t/rhnKgOqzmq0m

Since the robots.txt is virtual I Don’t know how to modify. Wista told me to install the wp-robots txt plugin. I did and I am not getting the correct result and wisita says as follows:

Hey Bob,

If you check out your website’s robots.txt file at https://annuity-lead.com/robots.txt, you’ll see that there’s some extra text on (and after) the line containing your video sitemap. Here’s the full text of your robots.txt file:
User-agent: *
Disallow: /wp-admin/
Disallow: /wp-includes/
Sitemap: https://app.wistia.com/sitemaps/44507.xml
<b>Parse error</b>: syntax error, unexpected T_STRING, expecting ‘,’ or ‘;’ in <b>/home/firstpa4/public_html/annuity-lead/wp-content/plugins/google-sitemap-generator/sitemap-core.php</b> on line <b>1770</b>

Based on what I see there, it seems there may be a problem related to your Google Sitemap Generator plugin. I’d recommend reaching out to the developer of that plugin for tips on fixing it. Once your robots.txt file is fixed, you should be able to verify it with no trouble.

Let me know if there’s anything else I can do to help – thanks!

https://www.ads-software.com/plugins/google-sitemap-generator/