Facebook ads after IOS 14.5 update

I've had some fantastic advice on the web but wanted to open this question to the whole community. One thing that is still puzzling me is targeting. I'm led to believe that one of the issues with iOS 14.5 is the inability for Facebook to track outside of the platform. This is what's confusing from my point of view, being in the wedding photographer i use basic targeting - age, gender, location and the only demographic is relationship status - Engaged, this has worked for years. All of the above targeting is available via facebook data so don't understand why results are down. I have tried this week running a very successful ad from 12 months ago, identical in every way. Fatigue isn't the issue as with it being within the wedding industry, clients change, they go from engaged to married and newly engaged couples replace my target audience. The previous 5 years of February have been the busiest month for bookings, however, this year we have had zero bookings. All seems very strange to me.

Any clarification would be amazing.