My Sandisk will not charge past 22% and I have charged it for 48 hours. It quits during my wrkouts. Frustrating.
I would try a different USB cable for charging.
Equally (or more) frustrating is someone looking for help or answers, yet only writes “My Sandisk will not charge past 22% and I have charged it for 48 hours.” 
No one can give you help or an answer unless you first give more details about your problem and circumstances. For instance:
What model is it?
How old is it?
How often do you use it?
How long has it been doing this?
What are you using to charge it with, AC-USB charger or computer?
Desktop or laptop?
What is your usage & charge routine?
While the suggestion of a new cable is certainly good, there are many other potential reasons for your issue. But without you telling us more, we won’t know.
