Why was chargaff not included in the noble prize?

Chargaff's work laid the foundation for the discovery of the double helix structure of DNA, but his contributions were not directly recognized when the Nobel Prize for Physiology or Medicine was awarded to Watson, Crick, and Wilkins in 1962 for their discovery. It is speculated that Chargaff's exclusion may have been due to his controversial personality and his strained relationships with other scientists in the field.