If an instance of circular reasoning is defined objectively then there is no break, and infinite regress is a form of circular reasoning.
If you want to know how there is a here & now: a determinate point, this needs to be considered subjectively because the here & now is part of subjectivity, which is finitely bound by birth and death.
The mistake is to try to interpret the subjective here & now in terms of objective ideas, those created from subjectivity; "reflected light" as Heidegger puts it:
Dasein is inclined to fall back upon its world (the world in which it is) and to interpret itself in terms of that world by its reflected light, … GA 2, H. 21