I have a honda unicorn 160 2021 bs6 model and while starting the engin

I have a honda unicorn 160 2021 bs6 model and while starting the engine revs up and will continue for 2 to 3 minutes. I have consulted some mechanics and even the honda showroom but nothing changed.showroom people tols me that new bs6 engines are like that only.is it true?

Need help or advice? Ask your question and get help from experts