Is chapter 30 a re-upload? I think I've read it in previous chapters???

There are two versions of this manga in the webpage.

One is very advance but the translations are non-official.

The other one is this one, with good cleaning and translations.

Oh you are right! I've been reading the other fan translation the latest is up to chapter 52. But I must tell you, the fan translation is quite good though.

Nowadays, some scalation groups are sincerely great.