Several Decades Submerged
One of the many advantages of running a submarine on nuclear power is that it can go for decades without needing to stop for refuelling. This is only one of the advantages. For instance, the nuclear submarines of the Astute class operated by the Royal Navy only require refuelling once every quarter of a century.
If a submarine is provided with such capabilities, it will be required for the vessel to surface in order to replenish its provisions with new supplies. This will necessitate the vessel coming to the surface more than once. Even so, the fact that this is the actual circumstance is mind-boggling, despite the fact that this is the case.