It was in a tournament but both players already qualified for the next round so it didnt really matter.

Found the wikipedia source:

On 15 March 2021, GM Magnus Carlsen, playing white, led with the Bongcloud in a game against Nakamura at the Magnus Carlsen Invitational. Nakamura mirrored the opening with 2…Ke7?, leading to a position nicknamed the Double Bongcloud.[2] The game was intentionally drawn by threefold repetition after the players shuffled their kings back and forth, and the opening was later jokingly named the Bongcloud Countergambit: Hotbox Variation. The game occurred in the last round of the preliminary stage of the tournament, and both players had already qualified for the following knockout stage, making the game a dead rubber. It marked the first recorded occurrence of 1.e4 e5 2.Ke2 Ke7 in a major tournament.[2][7]