Sniffer script not working ros 5.19

RouterOS Scripting
1

any ideas why this isnt working?

:local a “test”;
/tool sniffer set file-name=/usb1/$a;
/tool sniffer start
:delay 300
/tool sniffer stop


if i change the $a to anything else it works, this is what im truly going for:

:local a [/system clock get date];
/tool sniffer set file-name=/usb1/$a;
/tool sniffer start
:delay 300
/tool sniffer stop

tks

2

put filename in quotes and make sure there arent any special characters in there (like slashes and colons).