Save Settings Button Missing in Subsite

Hi! I have setup a WordPress Multisite and installed Easy Mailchimp Forms. It works great on the main site. However, on the subsite, I cannot setup or save my API key because the “Save Settings” button is missing.

I tried deactivating and reactivating the plugin but the save button still does not show up.

I hope you can help.

https://ww.wp.xz.cn/plugins/yikes-inc-easy-mailchimp-extender/