Lamar's second week at No. 1 fends off a challenge from Imogen Heap's "Headlock." By Kevin Rutherford Kendrick Lamar’s “Not Like Us” rules the TikTok Billboard Top 50 chart for a second week in a row, ...

"TikTok may be temporary but TiK ToK is forever," she wrote over the selfie-style clip. The 2009 track gave the star her first Billboard Hot 100 No. 1 – and the first No. 1 of the 2010s.