I reshaped the die to this form and could cut thread. However comparing to proper one still the cutting edges were not seemed good. I may try further shaping later.
I have some dies from the same manufacturer “SKC”. M3 in them had a problem as well. I ground it as same as M1.7, but it did not cut in at all. This manufacture, “SKC”, is real crap. I will never buy anything made by “SKC.”