If it's any consolation, I've had my halfling character roll a natural one on an ability check she had with advantage, and I've had it happen at least once on at attack roll in combat as well. Four 1s in a row is pretty darn poor luck, but it's slightly more likely with Larian's RNR than it should be. The inverse is true as well - high rolls have a higher chance of being followed by other high rolls as well.
I will say... I've been at a table where a player using psychical (tested as fair) dice has literally been playing a halfling and rolled double natural 1s on at attack. I've seen it happen once, exactly, in my table-top history, but I have seen it... It can happen. But you will see it happen more here in this game than you will outside of it, and that is a problem that their "Ha-ha, You're a cheater" dice check box doesn't actually fix.
