The white gasket of the internal seal is worn.
Disc fastening screws are loose.
If 1 and 2 are checked and measures are taken, but there is still leakage, it can be judged that the sealing surface in the cylinder body is damaged.
The inner sealing surface of the barrel is damaged, and the problem is serious. The suggested solutions are as follows:
1) shall be repaired by the manufacturer within the warranty period.
2) If the warranty is issued, the maintenance cost will be very expensive, so you can consider replacing the gun with a new one.
3) There are new guns on the market, one of which has an innovative patent, and the inner seal has a longer service life, and the inner gasket can be replaced for more than 2 years.