chartboost for mobile game monetization: am i missing something?

hey everyone, realy hoping for some guidance here. i just launched my first proper hyper-casual mobile game on android, and i’m trying to figure out the whole mobile game monetization thing. i’m a complete noob when it comes to ad networks, but i’ve heard good things about chartboost for indie games, so i decided to start there.

i followed the chartboost sdk integration guide for unity pretty meticulously. i’ve got both interstitial and rewarded video ads implemented and they seem to be firing correctly in my tests. i even made sure to initialize it properly and handle ad callbacks.

the problem is, now that it's live (albeit with very few users so far), i'm seeing super low eCPM numbers, and the fill rates are all over the place, sometimes zero for certain regions or users. i feel like i'm missing a fundamental concept or setting in the chartboost dashboard or maybe even in my integration. it's realy frustrating becuase i thought i had everything set up according to the tutorials.

i've tried tweaking the campaign settings a bit, like ensuring it's not in 'test' mode and playing around with some basic geo-targeting, but nothing seems to make a significant difference. i even double-checked my app ID and signature multiple times. i've also looked through a few old forum posts on other sites, but they mostly talk about more advanced optimization or older SDK versions.

so, for someone completely new to this, are there common beginner mistakes with chartboost integration or campaign setup that lead to such poor performance? what's a realistic expectation for eCPM and fill rate for a brand new, small game using chartboost? any crucial dashboard settings or optimization tips for a complete noob trying to navigate mobile game monetization? is chartboost still a solid starting point for indie developers, or should i have jumped straight into ad mediation?