Why is my Vauxhall Zafira Life's fuel consumption increasing?

I've noticed that my Vauxhall Zafira Life's fuel consumption has been steadily increasing over the past month. What could be causing this issue and how can I improve my fuel efficiency?

It is important to regularly check and replace your air filter. A dirty air filter can decrease fuel efficiency and increase fuel consumption.

Make sure your tires are properly inflated. Under-inflated tires can decrease fuel efficiency and increase fuel consumption.

Avoid aggressive driving and try to maintain a consistent speed while driving. Sudden accelerations and braking can waste fuel.