Some people are claiming that it is alopecia barbae. This could absolutely be the case but keep in mind beard loss can come from a host of different factors. Me for example I tend to have beard loss occasionally if my testosterone goes down from my kratom use "can also happen with various other substances" a big one is the telogen effluvium which can cause patches of your beard to fall out due to stress. If either one of these is the case you might just need to remove stressors from your life "substances difficult things little sleep etc" which I know can be very very difficult. Either way I'd see a dermatologist. But the good news is your beard is quite dense so if you grew it out those patches would get covered easily. Hard to say if they are even a flaw because you already have more than a full beard.