Broken extractor interfering with chambering? Or just dirty?
Broken loaded-chamber indicator interfering with chambering? Or just dirty?
Is the gun really, really clean? Detail strip it and clean all the gunk and old lube out of it.
An old toothbrush helps.
Use the old toothbrush to clean the extractor hook and the loaded-chamber indicator, without having to strip the gun.
When you detail-strip it, look for broken or bent parts.