Lotka is a child of the Ruhr region. Born in Duisburg, he played for local club MSV up until he was 13. A year with FC Schalke 04 was then followed up by two seasons in the Rot-Weiss Essen youth academy, after which Lotka spent his final three seasons in youth football with Bayer 04 Leverkusen. Ahead of 2020/21, the 1.90m-tall custodian became the reserve goalkeeper for the Hertha BSC second team in the Regionalliga Nordost. During a one-and-a-half-year spell up until December 2021, he made 11 appearances.
Due to injuries and illnesses to Nils Körber, Oliver Christensen and Rune Jarstein, the goalkeepers above him in the club's pecking order, Lotka made the first-team bench on Matchday 21 of the 2021/22 Bundesliga season. When Alexander Schwolow was also ruled out in the run-up to the game away to SC Freiburg on 26 February 2022, Hertha's fifth-choice goalkeeper debuted between the sticks. Although the match ended in a 3-0 defeat, and both Christensen and Schwolow subsequently returned to the fray, then coach Tayfun Korkut stuck with the "carefree" Lotka, who did however lose each of his first five Bundesliga matches. He briefly lost his position between the posts after the change of coach (Felix Magath replaced Korkut), but returned to the fold after Schwolow was ruled out again from Matchday 28 onwards.
Thanks to a string of strong performances, Lotka played a major role in his team's victories away to Augsburg (1-0) and at home to Stuttgart (2-0), where he saved a total of seven shots from the opposition. kicker magazine gave Lotka an average rating of 3.25 for his performances in those 10 Bundesliga appearances – putting him 0.2 points ahead of Hertha's established goalie Schwolow. In the final match of the season, a 2-1 defeat away to BVB, the 21-year-old suffered a concussion and missed the promotion/relegation play-off matches against Hamburger SV. Lotka sustained the injury when he collided with the goal post shortly before half-time.
Lotka, who has dual German and Polish nationality, has represented his parents' country at international level from the U17s onwards.