Help with Instagram, especially with adding photo captions

iOS & iPadOS

I added a photo to Instagram and got to the place where it asked about adding a caption; I double-tapped and was able to type, but VO did not read letters as I typed or deleted them and also did not read words. When I finished the caption, VO read nothing except an "OK" button. It seems that the app is the one and only way to use Instagram, and surely someone out there is making this work. Please advise. Thanks for any assistance.