Reboot the phone, just in case.
Look up what the minimum temperature for fast charging is supposed to be (I think you are saying that it's fast charging that has stopped, not all charging). What temperature does the system think the battery is at?
Is this the original battery or a replacement? I once met a replacement battery that didn't have a temperature sensor at all (just hard-wired to report the same temperature regardless) - I sent that straight back as it was obviously not the genuine battery it was sold as. Point is that some replacement batteries are unreliable.