The US House of Representatives is demanding testimony from representatives of Instructure, the twice-hacked company that owns the education platform Canvas. Lawmakers are seeking answers to explain the company's delayed response to cyberattacks that enabled bad actors to scrape the personal information of millions of students and teachers nationwide. Instructure revealed this week that it had reached a deal with the hacker group ShinyHunters, under which the hackers would destroy copies of user data and agree not to extort users. ShinyHunters had hacked the platform first in April and again last week, and claimed to have targeted thousands of universities and school districts.  The House Homeland Security Committee said it is investigating the hack alongside the Cybersecurity and Infrastructure Security Agency.…