Ackermann started playing football as a five-year-old in Azalea BK. Ackermann then went to IFK Göteborg, where he spent seven years.[1]
On 14 August 2017, 16-year old Ackermann made his debut with the senior team in Allsvenskan in a 2–0 home against GIF Sundsvall, coming on as a 92nd-minute substitute for Chisom Egbuchulam.[2]
In November 2018, Häcken accepted a bid for Ackermann from the Italian ACF Fiorentina.[3] However, during the medical examination it was discovered that Ackermann had a heart defect, which stopped the transition.[4] He underwent an operation in Belgium on April 30, 2019 that fixed the heart defect.[5] In August 2019, Ackermann returned to Häcken and was able to start training with the team again.[6] He did not play any competition matches during the 2019 season, but in November 2019 he was selected for the first time in a year in the squad for a training match against Ljungskile SK.[7] After the 2019 season, Ackermann and Häcken agreed to terminate his contract early.[8]
On 3 January 2020, Ackermann was acquired by Örgryte IS, where he signed a three-year contract.[9]