SYSFILES Error With Dbname

I have databse called RM-A1 and a log of RM-A1.log

When i run this statement it errors.

select ceiling((size * 8192.0)/(1024.0 * 1024.0)),
case when status & 0x100000 = 0 then
convert(varchar,ceiling((growth * 8192)/(1024.0*1024.0)))
else convert (varchar, growth)
end + char(10)+char(13)
from RM-A1_log.dbo.sysfiles where fileid = '1'
--This works
select * from dbo.sysfiles

Im using a dynamic statement

set @cmd = N'select @ceil = ceiling((size * 8192.0)/(1024.0 * 1024.0)), @CNT = case when status & 0x100000 = 0 then
''MB '' + convert(varchar,ceiling((growth * 8192)/(1024.0*1024.0))) '
+ 'else ''PER '' + convert (varchar, growth) '
+ 'end' + char(10)+char(13)
+ 'from ' + @l_db_name + '.dbo.sysfiles where fileid = ''1'''

exec sp_executesql @cmd, @retType, @cnt OUTPUT, @ceil OUTPUT


I cannot determine why log name of '-' are erroring all other databases are working.