Topalloj joined the Millwall academy aged fifteen, progressing through the academy to captain the under-21 side.[3] In September 2022, he joined National League club Dagenham & Redbridge on a one-month loan deal.[4] Having been training with the first-team, Millwall manager Gary Rowett explained the need for first-team minutes as the driving factor behind the loan move.[5]
On 23 December 2022, Topalloj returned to the National League, joining Bromley on an initial one-month loan deal.[6] On 19 January 2023, he joined the club on a permanent deal.[7] Following the move, he credited the desire to play regular first-team football as the driving factor behind leaving Millwall.[8]
Having lost his place to Idris Odutayo toward the end of the 2023–24 season, Topalloj failed to make the matchday squad as Bromley defeated Solihull Moors on penalties to earn promotion to the English Football League for the first time in the club's history.[9] Following promotion, he signed a new contract.[10]
On 22 November 2024, Topalloj returned to the National League, joining Sutton United on loan until January 2025 with the view to extending until the end of the season,[11] a clause that was subsequently activated.[12]
On 18 July 2025, Topalloj joined National League side Hartlepool United on loan until the end of January 2026, with the option to make the move permanent.[13]
On 2 January 2026, Topalloj has his contract with Bromley terminated by mutual consent.[14]
On 7 January 2026, Topalloj returned to National League club Sutton United.[15]