I removed the BME module per BME Troubleshooting (temperature, humidity, pressure, and VOCs) because my Flex is reporting PM#s but temperature, humidity, and pressure were all 0 or close to it while the VOC readings simply didn’t make sense.
I decided to pull out the PMS6003 packs and vacuum while I have it down then noticed the battery. Is the CR2032 used for anything other than Vbat for the DS3231 and would it be worth replacing it to try and get my BME sensor working again (I2C master/slave stuff) – before I contact you all about a replacement?