It is good that one is fearful that occasional acts of offence will affect prapatti from yielding the desired results as this will ensure one remains without committing misdeeds. One must not be casual that having performed prapatti will yield the benefit regardless of one’s behavior. In this matter, one must be apprehensive and be worried that committing sins will result in punishments.
But one need not be fearful whether one’s sharanagati will yield the desired benefits. This is what Svami Desikan says “nibharO nirbhayOsmi”.
You are not fearing what should be feared and are fearful of those that need not be feared. You not need have any worries about sharanagati, as its performance entrusts the responsibility to Bhagavan. It is wrong for many who question whether it will grant moksham.
Sharanagati is a mark of us surrendering us and the responsibility for our protection; we need to remain unworried about this. If we still are perturbed, it implies that we have not surrendered our burdens properly.
Those who have rendered sharanagati must avoid questions about whether it will yield fruits if one were to transgress. After having performed sharanagati one must be peaceful that that Bhagavan will take care of us. But we must be worried about committing sinful acts as they will certainly result in punishments.
Hence, those who have performed sharanagati need not be worried about whether it will fructify, whatever happens. We will remain unconcerned about the affairs of others; similarly, the soul belongs to Bhagavan and one must remain unconcerned about the wellbeing of the soul; but one must be worried that misdeeds will lead to punishments.