This indicates that the film did not get exposed, 1 check next time that the film is engaged in the take-up properly, one way to check once loaded with film ,carefully rewind a little on the rewind knob till you feel it tightens be careful that you don't rewind the film into the cassette I usually do this with the back open. There is enough leader to do this. close the back and watch the rewind for movement while advancing the lever. If the rewind knob moves success. 2 Even if the film moved therre is the possibility that the shutter is in need of repair then you have to send it out for repair. 3 If light is getting to the film the negative will be darkened. This is true of all negative film. Transperancy or slide film is just the opposite. 4 Make sure that you are loading and rewinding in darkened room. It doesen't have to be pitch black just not in sunlight. 5 And lastly there could be deteriorating of the light seal around the edge of the film chamber. If you suspect this, seal the camera back with black gaffers tape . Don

Hello

This problem could have a number of causes,

To check to see if it is a camera fault of developing fault you could try using a cheap colour film in the camera and getting it developed at a normal photo processor.
This will determine in which half of the process the fault lies.
If the pictures from the colour film are the same then it must be a camera usage problem or fault.
If the pictures are ok from the colour film then it will be a problem in either the film being used, developing problem (poor mix of chemicals etc).

This will just speed up the diagnosis a bit.