Tween not working properly?

Godot Version

4.3

Question

Im new to godot and I am working on a leveling up system. I want to add a tween to the progress bar so it moves smoothly whenever you gain exp. But whenever I add exp the tween only goes ~3/4 of the way is is meant to go. Like I said I am new to godot so it may be simple.

(I apologize if it is not in code formatting I looked around for a while but could not find anything on how to do it)
Here is the piece my code not working:

var tween = get_tree().create_tween()
tween.tween_property(bar, "value", exp, 1)
#bar.value = exp
counter.text = str(exp) + "/" + str(exp_for_level_up)

i would like to know the specifics of your bar and the values.
What is the bar’s max_value and what value is given to exp?
You said it only fills up 3/4 of the way, so could you check if the values are the same or if there is a weird max_value or step property configured.

The first max_value is 100 then it gets multiplied by 1.15 each level. EXP starts at zero but if you press a button it goes up by 5. I have tested the progress bar without the tween and it displays the correct value so I assume it is a problem with the tween I made.

Here is all of my code in case you need anything else:

extends Control

@onready var text = $LevelText
@onready var bar = $LevelBar
@onready var counter = $expCounter

var level = 0
var exp = 0
var exp_for_level_up = 100

func _ready() → void:
#PLANNING TO ADD A SAVE/LOAD FEATURE
#SETS VARIABLES TO SAVED DATA
bar.value = exp
bar.max_value = exp_for_level_up

counter.text = str(exp) + "/" + str(exp_for_level_up)
text.text = "[center]Level: [/center]" + str(level)

func _process(delta: float) → void:
#HANDLES LEVELING UP AND VISUAL REPRESENTATION OF EXP

if exp > exp_for_level_up or exp == exp_for_level_up:
	#IF THE exp IS GREATER OR EQUAL TOO exp_for_level_up FOR LEVELING UP IT RESETS THE EXP AND GAINS A LEVEL
	exp = 0
	exp_for_level_up = round(exp_for_level_up * 1.15)
	bar.max_value = exp_for_level_up
	print(exp_for_level_up)
	
	level += 1
	text.text = "[center]Level: [/center]" + str(level)
	print(level)
else:
	#SETS THE BAR AND exp COUNTER
	var tween = get_tree().create_tween()
	tween.tween_property(bar, "value", exp, 1)
	#bar.value = exp
	counter.text = str(exp) + "/" + str(exp_for_level_up)