You need to search for threads, there are lots of threads about it already.
https://www.blackhatworld.com/seo/m...ts-to-be-updated.991457/page-36#post-12202327
I get dm block even after 4-7 dms
It depends
sometimes i can send up to 30 DMS and sometimes just 6
its weird
20 to 30 , keep min 1/2 and 1 hour gap between each DMs