charging pins are corroded

@waltwlms they might be replaceable but are definitely not readily available. I would start by cleaning those with some distilled water/vinegar 50/50 mix and a couple of cotton swabs. Since those contacts are most likely nickel plated, the corrosion destroyed teh nickel plating. It is most certainly tedious since there is not a lot of room. Once the corrosion is removed, clean any residue with distilled water and cotton swab only. Apply a small amount of grease or some stuff that is called NO_OX_ID (not cheap and you would only need a very small amount so that could be overkill unless it is available to you) After that make sure that your charging base stay relatively dry.