Robots.txt is not available

I ran my weekly site audit for https://superbsalt.com on Ahrefs and got a message saying that my robots.txt file is not available. I also got a message from Google Ads, as I was applying for AdSense, to say that they also could not access the robots.txt file. However, the website is still visible on the web.

I have run a couple of checks through various website checkers and it looks like the robotos.txt file is okay and nothing is being blocked.

I also spoke to my hosting provider (Ionos) who said it is nothing at their end.

I removed the WP Optimise plugin that I recently downloaded to my WordPress site, and I also reinstalled a previous backup from a few days ago, but nothing seems to be working.

Any ideas people?

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