Clamp SIP problems

After 3000 miles and two years installed on the bike to get more game started the brake lever as if tubiese air, I changed the brake pads and I bled but the problem is, I wonder if they have had internal problems with this clip:

 http://www.sip-scootershop.com/en/products/brake+calliper+sip+for+grimeca_56401000

 I wonder if you have any type of warranty because my client asked me a warranty replacement brake caliper.

 I hope to hear from SIPSCOOTER.

Thanks

please help me, is possible repair this problem with http://www.sip-scootershop.com/en/products/gasket+set+sip+brake+caliper_56409000   or    http://www.sip-scootershop.com/en/products/gasket+set+sip+brake+caliper_56409100