Assign values to HMI tags in factory talk view SE using VBA

Using VBA I am trying to assign a value to my HMI tags.
The tag name is Alarm_TM. Once this tag value is set to 1, this triggers an animation on the HMI
Here is is my code so far

Public Sub auto_open()

gTagDb.getTag("_internal\Alarm_TM").Value = 0

End Sub

Whether I set the value to 0, or 1 the animation is not changing which tells me the tag value is not assigned.
What is the proper way of doing this?

Create a tag group, add the tag(s) you need to the group. Then make the assignment, and use the "WritePendingValues(TagsInError)" method of the tag group to update them.

Tag_str = "{[" & IOTopic & "]MyDigitalTag}"
Set HMITag = MyGroup.Item(Tag_str)
HMITag.PendingWriteValue = 0
Results = MyGroup.WritePendingValues(TagsInError)