Hello again Hilary,
There doesn’t appear to be anything alarming about the way you have set up your schematic as it aligns well enough with the datasheet. Perhaps there may be a layout issue with your board? Ensure that you have adhered to the following as specified in the MP2760 datasheet:
If your issue is not addressed from this, then perhaps there is some initialization or register setup issue that is limiting your current in which case I would encourage more in depth support with the engineers at MPS Now Technical Support.
Best,
Krishan