Low volatge from 3.3v pin when using battery (SAMD51 Thing Plus)

I’m trying to power a BMP280(3.3v) pressure sensor on battery, it works fine when plugged in with the battery attached. If I detach it from usb with the batt plugged in it continues to run fine. If I try to start it on just the battery the code hangs and it will not start the sensor. My multi-meter reads 2.5ish volts on battery and 3.3v when plugged in to usb. Ive used two different fully charged 3.7v LiPo cells 280Mah and 80Mah. Ive also used a charged Samsung 18650 that can put out 20amps and it still wont start the sensor. Even swapped sensors and nothings working.

I’m stumped any help would be awesome Ive scoured the internet for a day and found zero

Share a photo of the setup & wiring

the 280mAh & 80 are probably too small to push enough current; what voltage does the 18650 show? While using 18650, what voltage is showing up @ board?

I figured it out, sorry it took me so long to respond my notifications ended up in spam. Anyways it was something in my code but IDK what it was. I used a different example sketch from a different library (DFRobot_BMP280.h) and after some editing I manged to get my code to run with no problems. All I added to the example was a way to blink 13 after initiating the sensor which it wouldn’t do in my previous code. Then I verified the voltages and everything is fine I’m no loner seeing the drop in voltage.

I don’t see a way to mark as solved but its solved even though I’m not sure what exactly fixed it.

Thanks for the response, I was convinced i fried my board/sensors somehow.