Galaxy S9+ does not pop up Message+ texts

I have pop up over lock screen enabled, but when a Message+ text comes in, it does not pop up. It works fine on my Galaxy S21+ with the exact same settings. Any suggestions appreciated. Thank you.

Re: Galaxy S9+ does not pop up Message+ texts
Customer Service Rep

Please note that due to the older software that is on a phone like the S9+ when compared to the S21+, the pop-up on lock screen effect may not be something that is achievable on that device. 

Let's look into this further though, may I ask if you've ever had it work on the S9+, or was this something you looked into because it was available on the newer phone?