Nifas and prayer, plainly

A woman in nifas does not pray. And she does not make those prayers up afterwards. There is no prayer debt from nifas.

That is not a lenient reading and it is not a modern convenience. It is the settled position, and the basis for it is the report in the previous step. The reason usually given for it is worth having too, because it is a reason of mercy rather than of exclusion: al-Nawawi, quoted on islamqa in fatwa 49848, gives it as volume and repetition. The prayers are many and repeated, so making them all up would be too hard, unlike the fast, which comes once a year.

If you have been counting, stop counting. If somebody has told you to make them up, they are mistaken, and you can say so gently or say nothing at all.

The edge cases are real and they are where a scholar earns their keep. Bleeding that stops and then restarts. Bleeding that carries on past the maximum. On what that maximum is, the scholars genuinely differ, and here is how rather than merely that: the preponderant view is forty days, some hold sixty, and others hold there is no upper limit at all. Where a maximum is held and the bleeding passes it, the continued bleeding is classified as istihada, which does not suspend prayer, unless it coincides with her habitual menstrual timing. Those are the recorded positions, this platform picks none of them, and your own case goes to your own scholar rather than to a webpage. That is one question, asked once.