user65642: 

My pins are connected as follows; vcc-3v3, gnd-gnd, sda-A4, scl-A5.


user64075: Is it a 3.3 V only OLED? I suppose its vcc(OLED)-3v3(Nano).
Most OLEDs use 3.3V -5V where sometimes the 3.3V from the Arduino is not sufficient.If its a 3.3V only OLED could you give the make of the OLED (does it have jumpers to change I2C address). Normaly the I2C scanner should return at least with nothing found.

65642: <p><a href="https://i.stack.imgur.com/6A6Fq.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/6A6Fq.png" alt="i2c scanner serial monitor"></a></p>

<blockquote>
  <p>My pins are connected as follows; vcc-3v3, gnd-gnd, sda-A4, scl-A5.</p>
</blockquote>
 64075: <p>Is it a 3.3 V only OLED? I suppose its vcc(OLED)-3v3(Nano).<br>
Most OLEDs use 3.3V -5V where sometimes the 3.3V from the Arduino is not sufficient.<br>If its a 3.3V only OLED could you give the make of the OLED (does it have jumpers to change I2C address). Normaly the I2C scanner should return at least with nothing found.</p>
