Tiger wheel and tyre Meadowdale

I bought a continental tyre at Meadowdale tiger wheels last year and I was informed it came out with insurance.It developed a lump in March this year and I took it back.I was assisted and a new tyre was fitted.The new one has developed the same problem again.So I went back.This time I am told the batch number of the new tyre is not the same as the one on their system and therefore I cannot be assisted.I haven't changed tyre anyway and I feel they recorded a wrong serial number intentionally so I do not come and claim again.This is *****