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How old is your Lenovo Yoga, please?
OK. If it is over a year old, its warranty has expired. But, if not a good-quality product in this case, the battery may be defective, unfortunately.
If so, the battery will need replacing.
A question though: have you checked the charger, whether it is in good shape ? the cord not bent severely at any point, no dirt or grease on contacts, etc.?
Put the leads of the voltmeter across the output jack of the power charger, and plug it in (being careful not to cross the terminals nor the probes, though.)
What voltage registers? when you do this carefully.
That's hard to do, w/the small ones. Is it that kind?
I think the charger is OK too.
Would you like listings for replacement batteries, with their cost, for this Lenovo device?