Which PSoc5 LP KIT are your using?
And Are you using the debugger on board to program PSoC5?
I am using the cy8ckit-059 psoc 5lp board and using the attached programmer.
Have you set [ProjectName].cydwr -> Debug select as SWD?
And then please refer the kit's schematic, if there are any components added on SWD pins, please remove them.
In addition, this KBA is FYI,