How many times does a tech need to come out to fix seals ... how many times can taps be so so faulty!

We had our bathroom done last year and since we installed Tivoli taps and had our Cobra taps removed, everything went SOUTH. I have had Johan van Aswegen and Siyabonga here on NUMEROUS occasions as there is an issue with the seals. I have stopped counting how many times they had to come out to fix the issue. Its is sometimes the bath, then at times the basin. Currently we have almost no cold water coming out of our basin tap, but hot water is fine. If my disabled child gets scolded because of a faulty seal or tap system, I will sue Tivoli as I cannot take this anymore! You brag with a LIFETIME guarantee But this is getting REDICULOUS!