According to The Sun, Netflix honchos have recently had a convo with the ex-Royal couple ... supposedly telling them to make better, must-see content -- or risk not getting the rest of their $100-million-plus contract ... which they've already gotten about half of at this point.

Indeed ... the reported conditions have been set -- namely, Meg and Harry must produce higher quality shows, docs, and/or movies to claim the rest of their bag ... and if they don't, Netflix is apparently prepared to cut their deal short and refuse to pay 'em out in full.

The Sun goes on to say -- citing an unnamed source claiming to be plugged in -- Netflix was happy with the results for their bombshell doc ... but have been disappointed about everything after that, which presumably includes PH's forthcoming Invictus docuseries (which is still happening and coming out around August). Anything else though is nowhere to be found.

The report notes Meghan pitched an idea for an animated series about a girl inspired by historical female figures -- but that got dropped by Netflix. It would seem they didn't think it was compelling ... a recurring theme we're now hearing about them as creatives.

Now, on the prospect of potentially cutting 'em loose unless they deliver ... The Sun's source says the streaming giant wouldn't do it as publicly/humiliatingly as Spotify did. However, they do concede it would grab big headlines in and of itself ... and probably be a bad look.

No word on a timetable for them to make good on their deal, but it sounds like the clock is ticking for them. Gotta say ... this is not great news for Harry and Meghan. It would seem that wherever they've inked big-time deals ... the companies have been unsatisfied.

They're already filthy rich as is -- but if their Hollywood prospects are cut short ... that could seriously impact their financial futures in the long run. So, they kinda gotta get with it on ideas.