Q:
My colonist have the necessary materials in stockpile zones or shelves and enough medical skills to surgery. but show "Cannot cure: need material".

A :
If you schedule an surgery to cure a colonist and prepare the necessary medicine, but may not be able to perform the operation with the message "Cannot cure **** :Need material".

They are due to the patient not permitting the medication needed for treatment. Please allow the use of required medications on the Health tab.

The most common case is when glitterworld medicine is needed but the patient is only allowed medicines.