Heartburn 😭😭😭

Hello ladies! I am 34 weeks along and I have woken up 3 times this evening because of heartburn. It is so bad that I can actually taste the acid in the back of my mouth. Of course it goes away as soon as I sit up, took tums the first time and it helped long enough for me to fall asleep. I tried sleeping while sitting up/propped up (that's not happening). I don't know what to do! I have to start getting ready for work in 3 hours, does anyone have any advice? I need sleep 😭