2019 prius prime can only be charged up to 50%

It was around 11am this morning, I noticed battery of my Prime dropped from ~50% to 0% when I was dropping on local streets for about 3 miles. I didn't notice any error or warning. Once I got home a couple hours later, I started charging it. Guess what, charging stopped when the battery was about 50%. Does it sound like my battery is in trouble? I live in the San Francisco bay area, and temperate was about 90% at around noon, so it was not that hot. I will leave it cool down overnight and check if any luck in the morning. I have about 60000 miles on the Prime after 5 years, so mileage is not that high.

 

Giving battery the time to cool down overnight did seem to help, and I was able to charge it to 100% this morning. I just came back from a trip to a farmer's market, with about a few miles on local flat roads, and 16 miles on freeway, and I didn't see previous sudden drop from 50% to 0%. I need to keep an eye on it, hopefully I won't see such sudden drop often.

No, I haven't done any charging schedule.