A person who keeps small commitments earns confidence for larger ones.

People form their estimate of you from the small things because those are what they have available. Whether you replied, whether you arrived, whether the minor thing you promised happened, all of it is being used to predict how you will behave when the stakes rise. Nobody gets to demonstrate reliability on something large before they have demonstrated it on something small.

Take your minor commitments as seriously as your major ones for a month, and notice what starts being offered to you. If you want to be trusted with more, the evidence has to come from what you are already doing.