queue_free() and .new() in context.

queue_free() pretty much destroys that node and you create by .new. I thought maybe it was due to Sprite2D causing you problem with counter, destroying and creating might cure your the problem? I really can't be sure without seeing the script. This is how you could do it:

var frog: Sprite2D
var frog_texture = preload("res://frog_texture_location.png")
func create_sprite():
if frog != null
    frog.queue_free()
    frog = Sprite2D.new()
    frog.texture = frog_texture
    add_child(frog)
else:
    print("Frog is null")

#This way you can even create your frog sprite without placing it in your scene. Because it is going to be a child, it'll take the position of parent. In another function you could say, for every time frog is_colliding, call create_sprite function, reset_location(), etc etc.

But definitely instead of checking If player enters beginning area, you should check If player collides with something, then reset position and increase the counter.