Do you have Option Explicit at the top of every module (right under Option Compare Database)? If not, this (and worse) is what you can expect. This is a system level option that should be turned on in the vb editor Tools > Options > Require Variable Declaration. I suspect it is this line
field2.Value = Me.TruckNo 'want it to read field "TruckNo" that is assigned to record
but if you read my signature, you'll see that we shouldn't have to guess at which line the error occurs.
For those who are easily confused due to copious quantities of alcoholic beverages, being too early in the day, or having more gray hair than gray matter, let's ensure you want to reference a form control value since it might have a different name than its underlying field. In fact, IMHO, they should not have the same name. E.G. if the control is named txtTruckNo, you cannot use Me and refer to the underlying field name. If they are named the same, sometimes it causes strange results, but not the error message you're getting.
Again, since it's not early in the day, and it's too early for drinking in my parts, the reason why you need to specify where the error is must be the last reason given.
The more we hear silence, the more we begin to think about our value in this universe.
Paraphrase of Professor Brian Cox.