Check engine light came on after 2 weeks of buying replaced catalytic converter

What is your question?

at dealership 2 weeks later came on again but they would not touch it this time. Replaced fuel injectors at repair shop 1800 now a week later light came on again now the repair shop is telling me the converter needs to be replaced again at 2300. Any suggestions as still paying off the first repair? How long can it still be used with light on before it dies?