Replaced with bigger SSD -- now it's running slow/hanging

Hi all -

I’ve been reading through the answers and throughout Google to try and figure out what’s going on with my mac.

I replaced the original drive with a larger SSD (Aura) following the guide on here and another site. Now, my computer will be working fine at one point and all of a sudden slow down and often hang - sometimes with the beachball, other times not.

It’ll usually come back just fine after a little bit, but it never used to do this.

I read about the SATA cable being an issue in previous macs, but I don’t see anything like that for this model.

Any ideas?