Work on making your prep rounds more efficient - reinforcements and rotation holes. Try to play more passively instead of being aggressive, remember you're on defense. Hold more tighter angles and corners that catch enemies off guard, instead of angles which leave you exposed. Throughout the round, you only held angles for a few seconds before repositioning - so I'd work on finding comfortable positions you can hold for longer periods. Try to work on crosshair placement, there were several times you aimed waist level when repositioning.

Know your role and play more passively on defense. Utilize your resources - teammate positions, sound cues, cameras...