'03 LB7 Invalid Serial Data after EFI Live updates

So I have always had zero issues with tuning my truck since day one. Would accept a cal-flash, full-flash, stand-alone flash, etc. Well it sat with the batteries disconnected for almost a year while the engine was getting built. Here about a month or so ago was when I got it back up and running. Updated the EFI Live and V2 software to current. Ever since then when I go to do a cal-flash it says ERROR: "$0534 Invalid serial number" and displays the serial number as 00000000000. I've tried a full flash where it says it programs in a new EFI Live serial number but it apparently doesn't stick.

The past month I have just been doing a full flash every time up until recently when I tried doing my first flash with the V8 program. Even doing a full flash it will not get passed the missing serial number. I did a bit of research and it is sounding like my ECM may be TIS corrupt? But so far I have only read this happening to the '01/'02 ECM's? I've programmed my ECM a few times with TIS but have never had issues at all, and to add, hasn't been programmed with TIS in probably 3 years. So I don't understand why it would suddenly start acting up.

So to sum it up, the only thing that was changed from last year was the EFI Live updates and leaving the battery disconnected for 7-9 months. When the engine build was done I did a V7 full flash of the stock tune back in. Once the engine was broke in I went to do a V7 cal-flash of the same tunes I've ran in the truck for the past three years and every time it brought up the serial number missing error.

Any help is greatly appreciated!

My apologies as I put this in the scanning section, not tuning.