The battery life may differ depending on what you are doing (for example, playing games may be more intensive than video watching). However, 90 minutes sounds shorter than normal. Can you please contact us so we can learn more? Thanks. https://support.oculus.com/
my Oculus Go the battery does not last very long . Mind only last amount 90 min on a 100% charge
Before worrying to much try a few cycles of the battery, some of my Lithium batteries in other devices have increase capacity by a large amount over the first few charges.