The reason for the slow wireless charging is that wireless charging needs to transmit energy through electromagnetic induction, and the efficiency of electromagnetic induction is lower than that of wired charging, so the charging speed will be slower.
In addition, the distance between the wireless charger and the phone will also affect the charging speed, the farther the distance, the slower the charging speed. If you want to speed up wireless charging, you can try to shorten the distance between the phone and the charger, or use a higher power charger.