WishList Member standard functionality will redirect a member to the set After Login page any time they login.
There is an option you can look into that can adjust that functionality in order to direct a member back to the original content they were trying to access once they login.
Login Form on Non-Member Page
The Non-Members page is set in the Advanced Options > Global Defaults > Error Page section of WishList Member.
Users can click on a protected link and if they are NOT logged in, they are then directed to the Non-Members page.
The user is able to login and will then be directed to the protected content they were trying to access if you insert the Login Form Mergecode onto your Non-Members page.
You have the ability to add a specific Login Form Mergecode to any page or post which will insert the login form.
Login Form Mergecode: [wlm_loginform]
Adding that mergecode to the content section of a page or post will insert a login form.
Note: This does not need to be added to the HTML of a page or post. It can simply be added to the content area.
There is also a Mergecode and Shortcode insert option that appears on Pages and Posts when using the WordPress Gutenberg editor.
This blue icon appears on the Classic Block of the Gutenberg editor and is a quick way to add mergecodes and shortcodes to a page or post.
This will allow members (who are NOT logged in) who click on a protected link to be sent to the Non-Members pages where they can then login (using the login form mergecode you have placed on the Non-Members page) and they will then be redirected to the content they were trying to access.
Please keep in mind that this login mergecode must be included on the Non-Members page and members must login using that login form in order for the redirect work. If not, they will simply be redirected to the set After Login page.