Could be blockage or flame rectification

1) if the hob is more than a couple of weeks old it will be the thermocouple for that particular burner.
If it is less than a couple of weeks old as well as the thermocouple it can also be the control knob hitting the hotplate before it fully depresses the gas tap below it.
In short this is repairable.
你需要一个气体安全注册设备工程师neer and 3 thermocouples which are specific to the model of the hob.
As part of the job description also detail the make, model, serial number and product or enr
number

It could be an issue with the thermocouple. This is the safety device that tells your gas valve you have a flame present and allows gas to flow. It’s a little metal probe that sits in your burner. Thanks

This Gas hob has an issue with thermocouple(FSD) and need changing. This part will cost £30-£40 each burner (cannot use universal thermocouple)
then plus labour

So if this hob not too old, I would get it fixed.

Hope this help