I highly recommend zinc L carnosine (also sold as gastric soothe on Amazon).
I had a stomach ulcer years ago (overuse of NSAIDS) and proton pump inhibitors (omeprazole, proliosac) fucked me up. They actually make it so that your body is no longer able to produce the acid that breaks down food in your stomach. It may cause temporary relief, but these meds can cause long term damage that can mess up your digestive system.
Japan has been using zinc l carnosine with great success for over 20 years.
More info here:
www.ncbi.nlm.nih.gov/pmc/articles/PMC7146259/Aloe vera juice is also great for instant relief from heartburn.