Defining "TG" Unit names- help needed

Can you help me identify what "TG3930" and other numbered "TG" Units are in my two countries? I cannot correct the shortages if I don't know which units they are. All of my listed units on the War Screens show as being supplied. The error below is just one example from my Newspapers.

Army unit Garrison TG3930 in Accordia is not replenished

supply units are automatic
build more bases 4 off 4 def of land and air works
build more supply units
also increase ammo supply load