Can’t activate Woocommerce Coupon Box

I purchased the premium plugin and tried to input my license code in the free (installed) plugin but I can’t find anyplace to put it.

And when I try and upload the plugin zip file, I get this result:

‘Installing the plugin…

The package could not be installed. No valid plugins were found.

Plugin installation failed.’

I don’t want to delete the active plugin and try it again because I’ll lose all my customization settings.

Please advise.

Thank you!