Incorrect interest earned with Apple Card

What was beginning monthly balance and ending balance? The rate is 4.35% APY (Annual Percentage Yield). It would be approximately .36% a month.

If I invest $100 on January 1 and let it sit, no withdrawals and no deposits, I would have earned $4.35 on December 31.

I had honestly forgotten about my savings accrual these last couple months and just checked it. My interest every month was more like .5% so I called support. They opened a ticket and told me they would let me know what was going on within 8 business days. It is a good reminder to double check it each month as it may be more of a widespread problem related to Goldman Sachs.