You can try switching to a gentler shampoo such as L'Oreal Kids or Garnier, because they're made with sodium laureth sulfate (ingredient lab-proven to be gentler than other cleansers)

Reading your ingredients will help, especially if you folks don't have L'Oreal Kids or Garnier in the UK. Cleansing ingredients are listed second or third on the ingredient list. The first shampoo ingredient is water.

Basically the scalp overcompensates after the shampoo strips away its oil. The following cleansers are pretty harsh, and can lead to greasy hair. Avoid them if possible:

Sodium lauryl sulfate

Ammonium lauryl sulfate

Ammonium laureth sulfate 

Ideally, hair should be washed about 2-3x a week. Every day is usually too much, but for some people it works well. It also depends on your scalp, and whether you get itchy on the scalp between washes. If you can cut it down to washing only every-other-day, or every two days, that would be a real benefit if you're growing your hair out. Shampooing and scrubbing is a lot of wear and tear on hair, and hair is weakest and most prone to breakage when it is wet.

Hope this answers your question.

Anais