An investors job is to say no to as many pitchdecks as possible. That's simply what they do.
Why? To focus the resources on the most promising opportunities of about 2,000-3,000 they sift through every year.
How much time do they spend per pitchdeck? 2:30 Minutes.
When it is the first outreach - it is meaningless. Maybe they didn't see it. Maybe there was something that they didn't like right away.
It is meaningless. Keep calm. Keep meeting them and updating them every 6-12 months.
Often what is a no today, can be a yes in 2 years or with your next venture.