Sub form is not getting updated

[myhnews]

I have a combo box on my main form. The Link child filed and Link master fields are configured correctly. I cannot figure out why the sub form does not get update after updating the combo box. (The combo box also uses a function, the function is running but the sub form does not get updated)

I have attached a sample DB. I have spent several hours and redesigned the form, but no luck. I you can figure it out, please share it with me.
Thank you
Joe