My crown came

My crown came out six month ago & my dentist put it back, but I have been today and he said it’s still loose because it’s not connecting to the root proper and i will eventually end up losing it, it’s my front tooth so what options is there for mean. My right side next to my two front is a crown too but this seems ok , it’s my left crown next to my two front teeth there is a big gap too which makes it look like its bad but it’s not I hate smileing