Although, your circuit is for only programming device, I would still recommend utilizing a bypass/decoupling capacitor attached as close as possible to the Vdd (+5v) and Vss (GND) pins of the target device, a typical value of 100nF (0.1uF).
I would also recommend pulling MCLR/Vpp pin high with a 10kΩ resistor or reasonable facsimile.
I also utilize a protection diode to prevent migration of the high voltage Vpp to other devices on the circuit, however in this case it is not necessary as the target device is not in-circuit.
If you are sill having issues after implementing the above recommendations, try powering the target device using an external power supply rather than the PICkit and ensure PICkit power option is disabled, this can be particularly an issue with clone PICkits.
Also be aware, the PIC12F675 stores the oscillator calibration value (OSCCAL) in Flash and while most Microchip development tools restore/maintain this value during a complete erasure of the device, some third party development tools do not.
The following are typical minimal circuit for In-Circuit Serial Programming (ICSP):
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