I am only getting a single 2x6 and it is cut in half
Darkroom Booth | Documentation
Most dye sub printers like those made by HiTi, DNP and Sinfonia can not print a single 2x6 but must do 2 2x6s. They are actually printing a 4x6 and cutting that in half. The default in Booth when you choose a 2x6 print size is 2 but that can be overridden if you are printing to a printer that can print just 1 2x6. The solution is in the Output menu, change the quantity back to 2 (see below).