OPA376: OPA376 non-inverting connection problem

Part Number:OPA376

I try to use OPA376AIDBVR as high impedance non-inverting amplifier with gain=1 (repeater).

Inverting input is connected to output and non-inverting – to ground through resistor 500 Mega ohm. Power supply is +- 2.5 Volt.

Without any input signal the output voltage is about -1000 mV.

Short circuit current between non-inverting input and ground is about 150 microamperes instead of the expected femtoampers. I checked several copies of this chip and got exactly the same results on all copies.

Please explain what could be causing this problem and how to fix it.

Best regards.

Sergay.