I've been editing this video on the latest version of Premiere Pro (14.2.0) on my Mac (version 10.15.4) and the transitions which I've downloaded as a preset files were working fine until today? I've attached a screenshot of what the effect looks like now (it should be a 'slide right' transition), and also what it looks like in sequence.
I've not changed anything about it, it just suddenly stopped working today, but I've applied the transition on the adjustment layer and the base layer (as instructed by the video) onto the original clip. I've tried rendering it to see if it's just a program thing, but it's still appearing like that in rendered vids, I've also tried deleting the preset out and adding it back in, as well as deleting my cache, turning the laptop/program off and on, and reapplying the effect - none of which have worked. If you know of a solution I can try, please let me know!!
[Title edited for clarity by mod. They are effect presets used as transitions in the timeline]