Either your BIOS CMOS is corrupt or the battery for your BIOS CMOS has run out of power.
Since your laptop is operational, and that this only happens when running on the laptop battery, then it's most likely that your BIOS CMOS lithium battery needs replacing.
Your laptop manual should give you details on how to replace the lithium battery. Alternatively, the manufacturer's website usually provides laptop service manuals for users.
The battery is usually located underneeth the keyboard. Usually, you're required to pry out the keyboard to gain access. Otherwise, it should be on the underside underneath a removable panel.
|Desktop PC| |Macbook Air 13" (Mid 2013)|
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