AMP redirection error

I had once used amp on a website a long time back and then removed it after 2 months or so. I deleted the plugin. But didnt redirect the urls. Now after seeing amp urls in analytics, I am trying to redirect

I used this code in .htaccess –

// Redirect AMP to non-AMP
RewriteEngine On
RewriteCond %{REQUEST_URI} (.+)/amp(.*)$
RewriteRule ^ %1/ [R=301,L]

But nothing happens – it remains on the same page. ie it is not redirecting to the non-amp version. I also tried redirecting with the redirection plugin with the same effect. That is url remains the same : sitename.com/?amp=1/ redirects to sitename.com/?amp=1/

When i check the amp url on a website crawler it says – the canonical tag is pointing to the non-amp version.

Is there anything else i should do? I mean, if canonical tag is alright, should it be a problem.