Victoria Arduino Black eagle group water flow

i just installed Victoria Arduino Black eagle Volumetric, and one of the group heads was working fine and suddenly it stopped dispensing water and the machine give me ( Group dose error)!!!

Any one can help in this ?

Thank you

Did you install it yourself? You should have a VA approved technician do the work for you - to avoid these problems! Best to contact VA for the contact details of an approved technician.

The VA agent ( distributor ) installed it but they have no idea about this problem and its solution.

That sounds odd - sounds like the burden should be on them to learn/correct this issue.