It wasn't axed. In that print the magazine makes it clear it was the author's decision to end the manga. The author herself apologizes below. So it has nothing to do with sales or reception. I think the manga was actually well received.
Now why the author choose to cancel it, we might never know.
It is still corrected to say it was axed. And it's not impossible the author's decision relates to sales.
Volume one is still on sale. It would be stupid to cancel it because of that. A lot of manga only gets popular after some few number of volumes. I would guess the author found another opportunity where she can earn more/something she likes more and decided to pursue that instead. She does end with "might we meet again", what suggest she'll keep doing manga and I wouldn't be surprised if she's already working on something else.
Anyway, axed would imply the magazine forced her to cancel. If it was her own choice, she had enough room to at least finish a second volume and give it a proper end. Maybe it was circumstances beyond her control, like diseases or something, what's understandable. But if she shows up with a new story soon after this, I wouldn't trust her again.