Flavel weak/ blocked gas burners?

Flavel milano 100 range cooker.
The burners are very weak and one does not work. Some are not fully burning. I bought this cooker used and it has been standing without use for about 12 months.
There is 24 bar pressure at the meter and the cooker was plumbed in by a gas safe professional.
John, November 2022


done
Replace the burner jets.

Ejdj, November 2022