Moncayola was born in
Garínoain,
Navarre, and was a
CA Osasuna youth graduate having joined the club aged 10. On 3 June 2019, Moncayola renewed his contract with the
Pamplona club until 2021. He made his professional – and
La Liga – debut on 17 August 2019, starting in a 1–0 away defeat of
CD Leganés. On 28 November 2019, Moncayola further extended his contract until 2024, and scored his first professional goal three days later, netting his team's third in a 4–2 away defeat of
RCD Espanyol. On 8 June 2021, Moncayola signed a new ten-year contract with Osasuna, running until June 2031. Osasuna also confirmed that his release clause would be €22m (£18.9m) for the next two seasons, before being reduced to €20m for the eight following campaigns, and €8m if the club was relegated. ==International career==