The description of Entangling Infusion says:
Saving Throw: Reflex negates
Your kinetic blast surrounds your foes in elemental matter. Whenever a blast with this infusion deals damage to a foe, that foe becomes entangled for 1 minute. The foe can remove this condition as a standard action with a successful Escape Artist or Strength check (with the same DC as for saves against your kinetic blast) or by dealing an amount of damage to the entangling matter equal to double your kineticist level (the matter has hardness 0). If the foe was already entangled by this infusion and fails its save against a second instance of this infusion, the increased amount of elemental matter fuses to the ground, causing the foe to be rooted in place as though anchored to an immobile object.
(All the emphasis mine.)
The part in italics clearly tells that someone entangled by the infusion who is hit for a second time does gain a saving throw.
The first bold part tells that anyone hit by an entangling infusion gets a saving throw.
The second bold part, on the other hand, does not mention a save, but rather says that any damaged target is entangled.
When first damaged by an elemental blast with an entangling infusion, does the target receive a saving throw to avoid being entangled?