My name is Dale.
It sounds to me like there is a constant drain on the battery or the charging system is not functioning properly. To test for a drain, take a 12 volt test light and hook it between the Negative ( - ) Batery post and the Negative cable. If the light is real bright then there is a constant drain on the system A extremely dull glow is normal because of the computers residuale (Milli-Amp) drain. But a bright light means either there is something on, ( like a glove box interior lamp, a lamp in the rear compartment or dome lamp left on, etc.) If you find the bright light, start removing fuses (One at a time) until the light goes out and then you will have to trace down whatever is on that circuit. It is possible that a module (vehicle these days have lots of modlues) is malfunctioning and creating a drain. If you can jump the vehicle off to get it started and run it for say 30 minutes and then it starts OK then chances are (without running the alternator/regulator test) chances are that the alternator is good and you just have a drain that needs to be isolated.
Let me know if there is anything else I can do to help you resolve the issue.
Have a Blesssed & Productive Day !
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