Capitol Police Chief says he called for backup 6 times and got no response from anyone..Why?

Probably because a lot of police are Trumpsters and wanted the insurrection to carry on unimpeded. 

He said he did,  I have not seen any complete new stories about the events of that day. 

That's the kind of thing that can be expected from a planned attack by ANTIFA. It may or may not have been sanctioned by the Democrats, but it served the purpose of accusing Trump of insurrection (ignoring the fact that the Dems have been guilty of insurrection for the entire past 4 years) so that they could "justify" (and I use the term loosely) an immediate impeachment.

As with the COVID pandemic that ushered in social distancing mandates, lockdowns, a destroyed economy that included a tremendous number of job losses, and fraud-prone mail-in voting during the final months of Trump's administration, the timing was as convenient as if it had all been planned.

But ask anyone: "It all Trump's fault".