It’s possible that your body is just not reacting to the glass. We chose soda-lime based glass because it isn’t 100% inert… the body does tend to react slightly to the glass, and that reaction is to encapsulate the glass object with collagen and fibrin… but some people’s bodies just don’t do that.
Also some people have a limited window for their body to react after installation. The act of wounding the body to insert it triggers this hunt for foreign bodies within your body, and this results in the encapsulation process… but for some people the window on this closes shortly after installation, so if your chip doesn’t settle down immediately, after a short period their bodies just don’t ever recognize the glass and it just floats.