Kapp also skipped the German mixed team at the 2020 Winter Youth Olympics, finishing 8th after losing to New Zealand's Hunter Walker 7–4 in the quarterfinals.

Kapp would join as the third of the new German team skipped by Marc Muskatewitz during the 2023–24 curling season, alongside junior teammates Felix Messenzehl and Johannes Scheuerl.

The new team would have a strong showing at the 2024 World Men's Curling Championships, finishing in 5th place after losing to Italy's Joël Retornaz in the playoffs.

After winning the European Championships, the team qualified for their first Tier 1 Grand Slam of Curling event, the 2024 National, where they had a strong showing, losing in the quarterfinals to Mike McEwen 6–5.

The two were teammates at the 2019 World Mixed Curling Championship where their team won the silver medal.