What are effects if AZ or other states can't certify 2024 election

Pres. Biden & VP Harris term ends at noon Jan 20, 2025 (20th Amendment).

Can Congress certify the election results without all states/territories?

If not….

Who is President at 12:01 p.m. January 20, 2025?

A new speaker of the House?

Or does Continuity of Gov't kick in with someone else?

"In a stunning rebuke to Arizona’s Democrat Secretary of State Adrian Fontes, a federal judge has ruled that he cannot certify the results of the 2024 election if any counties withhold certification due to allegations of fraud."

https://loudobbs.com/news/federal-judge-blocks-arizona-democrat-secretary-of-state-from-certifying-2024-election-if-counties-withhold-certification-due-to-fraud/