Shama-il Tirmidhi Chapter 31, Hadith Number 6 (202).

Sayyidina Ibn Abbas radiyallahu anhu says, Whenever Rasoolullah sallallahu alaihe wasallam drank water, he drank it in two breaths.

In this hadith drinking water in two breaths is intended which apparently seems correct. Sayyidina Ibn Abbas radiyallahu anhu has stated in a hadith of the Prophet sallallahu alaihe wasallam, Do not drink water only in one breath, but drink it in two or three breaths. The minimum number of sips one can take is mentioned in this hadith. Sayyidina Rasoolullah sallallahu alaihe wasallam at times drank water in two sips to show that this was the minimum amount of gulps one could take. Another explanation may be this that in the hadith it meant that two breaths should be taken whilst drinking water. If two breaths are taken whilst drinking water, then all the water will naturally be drunk in three gulps. By this explanation there remains no contradiction between this and the last hadith.