Thats the kinda if thing i complained to my neurologist about and he said PTSD. Have you ran it past your medical team. Could be other stuff too maybe, so always best to get their input.

I have had a similar thing as a result of my PTSD and I am slowly regaining memory abilities by doing memory training exercises (you can look them up online) and I always put anything important into the calendar app on my phone as soon as I find out about it. Depending on what time of day the event is I may put the calendar reminder for the day before at the end of the day and then immediately set my alarm. I also title the calendar reminders with the fact that it is the next day at X time.

I have this problem. It's almost like I'm going along doing life and then boom quick flashback and then I forget everything I was talking about. I HATE it. Especially in public. I am just up front with people now. And I write stuff down right when it's told to me. And have many documents of organized notes for my life in my phone.

Thats all the stuff i have figured out as work arounds too over the years. Sometimes my train get derailed and a few seconds later its back other times might be half an hour or even days.