Ran seems angry as Shin’ichi basks in the media attention he’s getting for solving a difficult case. When Shin’ichi asks Ran why she’s angry, she points out that it’s because of Shin’ichi that her father’s been getting fewer case requests.
蘭 ：- 「
怒 ってなんかいませんよー！！」 - “I’m not at all angry!”
新一 ：- 「あれー？
蘭 の父 さん、まだ探偵 やってたのか？」 - “Huh? Your dad was still working as a detective?”
- Literal: “Huh? Is it that your dad was still working as a detective?”
Shin’ichi has the incomplete observation that Ran’s father is losing work taking cases because of Shin’ichi’s detective work.
Considering how bad Ran’s father is at being a detective, it’s surprising to Shin’ichi that he’s still in the detective business.
However, based on Ran’s remark, Shin’ichi reasons that her father must still be working as a detective. He puts this as a question for confirmation.