I presume the company readvertised the job because either they did not get (enough) quality candidates, or they prepaid for several postings. If so, you were either rejected, or placed in a long list of candidates and the company is slow. And then, you were asked about remuneration again because no one noticed you applied twice. Just answer the same so you ...
I don't want to be harsh, but they looked at what you said, and they didn't think they were going to get good value for the money.
They may be wrong, of course, but that doesn't matter.
It's really up to you to decide if you're willing to work for less. Nobody here is going to have a great understanding of the job market you're in, and your personal ...
I would recommend against giving out this detail. You do not need to tell them what you earn. You could brush it off with a remark like "I don't want to tell you so early on in the recruitment process; it could influence the negotiation".
I were to occasionally work a 6 day week
There is no need to get creative with this. It's perfectly normal to enquire about what overtime you can expect to get, and make it clear that you are open to doing extra hours.