I have lost 8 of my Triumph Seals in game despite claiming them. They are Chronicler, Wayfarer, Undying, Savior, Almighty, Forerunner, MMXIX and MMXX. I did claim them, and all the Triumphs associated with them are still completed in my Legacy Triumphs. I don't want them to be lost forever as I put in hundreds of hours into getting them all.