Strange sitemap appended to robots.txt file

I noticed that the url to my sitemap on rotobots.tx is exchanged to something in the format https://cdn.ywxi.net/sitemap/49603xx/1.xml

The only way for to override this is by switching off the plugin!! I like to turn off, but need to have my correct sitemap url on robots file. I am not sure where this strange sitemap url is coming from but it doesn’t look right!
Anyone has a solution?

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