The first thing I would suggest you do is ensure that you have successfully installed the complete MetaMask Extension file on your browser. For this purpose, you can easily install the updated version of the MetaMask on your browser from the official website. If that does not resolve the issue, try installing an update for your web browser. If you are using Chrome, you can install the Chrome browser update via the official website of Chrome browser.

Once you have done this, you have successfully installed the latest version of the MetaMask Chrome Extension on your browser. However, if you are unable to follow this process due to any reason, we suggest you first uninstall MetaMask and then install the extension one more time as a fresh MetaMask extension file. Further, you can import the wallet using its Secret Recovery Phrase.