UI button not functioning properly after first use [unity 5.1.1]

[KrypTik_Sweller 14]

The UI button is supposed to "decode" an engram similar to in destiny. What it is supposed to do(which it does fully the first time):

-delete the engram from player inventory

-randomly select a weapon from a list of weapons of the same class

-debug.log("decoded") right before menu pops up

-open a menu displaying an image of the decoded weapon

What it does every time after the first time:

-deletes the engram from player inventory

-opens a menu displaying an image of the weapon FROM the first time you decoded an engram

- no debug.log   (it only shows once in log while the rest of the script still opens the menu after that line when i press the button again)

 

here is a code dump of the public void called on when the weapon is decoded:

 

 public void DecodeEngram(string type)
    {

//deleting the engram after decode button pressed
        if (type == "Scrap")
        {
            PlayerInv.Engrams[0] -= 1;
        }
        if (type == "Common")
        {
            PlayerInv.Engrams[1] -= 1;
        }
        if (type == "Rare")
        {
            PlayerInv.Engrams[2] -= 1;
        }
        if (type == "Mythic")
        {
            PlayerInv.Engrams[3] -= 1;
        }
        if (type == "Dark")
        {
            PlayerInv.Engrams[4] -= 1;
        }
        Debug.Log("decode");

//debug ^^ and randomly selecting weapon of same class \/\/
        WeaponIndex[] allWeapons = FindObjectsOfType<WeaponIndex>();
        int totalOfType = 0;
        foreach (WeaponIndex cur in allWeapons)
        {
            if (cur.Rarity == type)
            {
                totalOfType += 1;
                weaponOfType[totalOfType - 1] = cur;
            }
        }
        int chance = Random.Range(0, totalOfType - 1);
        SelectedWeapon = weaponOfType[chance];
        EngramDecode.SetActive(true); //opens the menu
        WeaponIconImage.sprite = SelectedWeapon.WeaponIcon; //sets image in menu to selected weapon icon
    }

 

[OcularCash 1,051]

Is this a UI related question or a function related question?