If the text is not locked to the typographical grid (e.g. the grid setting is not applied neither in the current format, nor in styles in text), then it is rather likely that the text will not align to the page baseline grid. It's enough to have a column head in the text,  without carefully measured distances (between the last line of the previous paragraph and the column head, and between the column head and the next paragraph), to misalign the part of text.

On the following screenshot, the paragraph below column headline is misaligned. To fix it, you should provide an advance of the headline itself, or of the paragraph below it, high enough to bring the text back to baseline (actually, the lock to the typographical baseline is doing exactly the same thing - but automatically).

On the following screenshot, the text is misaligned due to the paragraph spacing of 6pt. The paragraph spacing should be either 0, or equal to the page baseline grid.