Switch to a different system. LifeTechnologies/ThermoFisher has an alternative to that. I used it to train interns to assembly and verify minioperons in 3 weeks, starting from teaching them how to hold a pipette.

You are not the only one to have a problem with a group from China. Recently, they have had to refund me almost half of the payment for a failed work.

Wieslaw Swietnicki thanks for your answer. We were interested in this system because it is really cheap. Gibbson/in-phusion are very expensive for Argentinian science budgets.

I would not recommend the Gibson system. It is underdeveloped as offered and should be shelved.

Chinese designs are very cheap but not always at the level you need them. To work out problems, they would have to pull the products from the market, develop more and reintroduce. As you can imagine, it would be suicide for them.