If you are using the WP Fastest Cache plugin on your site then do the following to make it work with Simple Membership Plugin.
1) Exclude the Login Page from Caching
- Go to the “Exclude” menu tab from WP Fastest Cache Plugin’s admin menu.
- In the “Exclude Pages” section, add a new rule to exclude the membership login page.
You can copy your membership login page’s URL from the settings menu of Simple Membership plugin.
2) Exclude SWPM Login Cookie
- Scroll down to the “Exclude Cookies” section.
- Click the “Add New Rule” button there and exclude the “swpm_in_use” cookie. See the screenshot below for reference.