Textbox value won't assign to variable

I was running tests on my software and found that some of the values it was producing weren't correct.

I decided to step through the code and noticed that the variables I had assigned to textbox values when hovered over said empty, even though when hovering over the textbox assigned to it, the value inputted by the user showed.

For Example,

n = BiTimeSteps_TextBox.Value

when hovered over said

n = empty

even though

BiTimeSteps_TextBox.Value = 2

when hovered over.

So say I have a formula shortly after, that says

d = n*2

n when hovered over says empty and d is made 0 when it shouldn't be.

Someone told me if I switch it around to

BiTimeSteps_TextBox.Value = n

it should be recognised but it is still not.


What could possibly be causing this?

Copy of my actual coding (I'm trying to price options using the binomial tree pricing method):

 BiCurrentStockPrice_TextBox.Value = S
    BiStrikePrice_TextBox.Value = X
    BiRisk_Free_Rate_TextBox.Value = r
    BiexpTime_TextBox.Value = T
    BiVolatility_TextBox.Value = sigma
    BiTimeSteps_TextBox.Value = n


Dim i, j, k As Integer
Dim p, V, u, d, dt As Double


dt = T / n ' This finds the value of dt
u = Exp(sigma * Sqr(dt)) 'formula for the up factor
d = 1 - u 'formula for the down factor

'V value of option

'array having the values
Dim bin() As Double 'is a binomial arrays, it stores the value of each node, there is a loop

'work out the risk free probability
p = (1 + r - d) / (u - d) 'probability of going up

ReDim bin(n + 1) As Double 'it redims the array, and n+1 is used because it starts from zero
'------------------------------------------------------------------------------------------------------------------------------
''European Call

If BiCall_CheckBox = True Then

    For i = 0 To n 'payoffs = value of option at final time
    
    bin(i + 1) = Application.WorksheetFunction.Max(0, (u ^ (n - i)) * (d ^ i) * S - X) 'It takes the max payoff or 0
    Cells(i + 20, n + 2) = bin(i + 1) 'to view payoffs on the isolated column on the right
    
    Next i


End If

'european put
If BiPut_CheckBox = True Then

For i = 0 To n 'payoffs = value of option at final time

    bin(i + 1) = Application.WorksheetFunction.Max(0, X - (S * (u * (n - i)) * (d * i))) ' European Put- It takes the max payoff or 0
    
    Cells(i + 20, n + 2) = bin(i + 1) 'to view payoffs on the isolated column on the right

Next i

End If

For k = 1 To n 'backward column loop

    For j = 1 To (n - k + 1) 'loop down the column loop

        bin(j) = (p * bin(j) + (1 - p) * bin(j + 1)) / (1 + r)
    
        Cells(j + 19, n - k + 2) = bin(j) '' print the values along the column, view of tree
    
    Next j
    
Next k

Worksheets("Binomial").Cells(17, 2) = bin(1) ' print of the value V
BiOptionPrice_TextBox = bin(1)

End Sub

Book3.xlsm

I hovered over the variables once i'd ran the software to see if my programming was processing properly.

I originally had it that way round and I tried to get a friend to help me and he advised me to flip and see if that helps.

I've tried declaring all the variables originally I had it as

dim S,X,r,T,sigma,n As Double

Then i changed it to declaring them individually and then scrapped it because the variables were still empty. What you can see are the remaining ones I didn't delete due to my indecisiveness as to what to do next.

And you have said exactly my point. All the variables are empty. They are assigned to textbox values, but when values are entered into the textboxes the variables still remain empty.

What could I do to possibly solve this?

Thank you so much. I've been worrying about this for hours!!!