Writer macro produces garbage when used in new document

I’m using LO Writer(5.1.0.3) on a Mac (OS X 10.11.3) and want a macro for a journal header: a horizontal line below which is the date and time. I created this using record macro (Insert-Horizontal Line); cr; Insert-Fields-More Fields Date; Insert-Fields-More Fields Time; cr. After a lot of fiddling, I was able to make this work. On a new document, though, running the macro (Tools-Macro-Organize Macros-mymacro) produces 42413.83 42413.83 underneath a horizontal line. Oddly, if I recreate the new macro in the new doc it works and also the old macro works. Yet once I close that doc and start a new one both macros fail. In the example I gave the “.83” is sometime incremented in subsequent tries as though it is trying to reflect the time.

I am not using a JRE to run the macro.

Thanks.