Regarding The Earnings Of A Cupper Sunan Abi Dawud 3423

Arabic hadith text
حَدَّثَنَا مُسَدَّدٌ، حَدَّثَنَا يَزِيدُ بْنُ زُرَيْعٍ، حَدَّثَنَا خَالِدٌ، عَنْ عِكْرِمَةَ، عَنِ ابْنِ عَبَّاسٍ، قَالَاحْتَجَمَ رَسُولُ اللَّهِ صلى الله عليه وسلم وَأَعْطَى الْحَجَّامَ أَجْرَهُ وَلَوْ عَلِمَهُ خَبِيثًا لَمْ يُعْطِهِ ‏.‏
Translation
Narrated Ibn 'Abbas

The Messenger of Allah (ﷺ) was cupped, and he gave the cupper his wage. If he had known it to be unlawful, he would not have given it to him.