Installation Fail & Won’t Update

First off I’ve been using the Mail Poet V.3 on WP V.5.6. Everything was fine until I went to update and the plugin disappeared. GONE!

I came back to reinstall, activated and all was back online. I didn’t lose any subscribers or my forms.

Now I updated and same result except now I’m unable to reinstall. I’m getting an “installation failed” notice.

Any help would be appreciated.