Re-sequencing a Playlist

I'm running LMS ver. 7.7.6 on a Synology NAS. I'm trying to re-sequence a playlist through the drag and drop method. LMS isn't responding to the changes I'm trying to make. The drag and drop method has worked for me in the past when I've had LMS installed on a PC. Is this capability disabled in this version of LMS, or is it related to the fact I have LMS installed on a NAS?

If so, can someone recommend a third party playlist builder/editor?

Thanks.