Not able to access sitemap

Currently i have moved my site from inmotion hosting to bluehost i have moved all the files to new hosting.. The problem right now i am facing is with sitemap.xml I am not able to see the sitemap of my website. When i write it seems to be blank but when check the source page of that url it seems in the source code.. I am using this plugin only.

I have even try to rebuild but getting error. “There was a problem writing your sitemap file. Make sure the file exists and is writable.”

Anyone please help how can i fix this issue

https://wordpress.org/plugins/google-sitemap-generator/