Over the years we have seen customers having trouble folding the Buzz. Mostly it's a combination of factors that make a Buzz a bit stiff.
Most important is that the main silver central tube must be clean and preferrably lightly lubricated. (Put some WD40 on with a rag.)
The second point of attention is the grey release knobs: Remove (blow out) any sand or debris and spray in some WD40. Especially the knob on the left that is slide-push needs this attention. (Left-right viewed in the driving direction.)
These grey knobs have to be pushed firmly to properly fold the chassis. (The left one is first-slide-then-push.) When it folds and gives a loud 'clack' you didn't push them in far enough. We know from experience that this sometimes remains difficult for some customers.
Later revisions of the Buzz have slightly larger buttons that are somewhat easier to operate.
Your front wheel probably needs some care. At the side of the black plastic front 'fork' that holds the wheel you will find a small hole. Rotate the front wheel until you see a small button come by. Push it with a pointed object. (A small screwdriver will do)
You can now remove the front wheel from the black front fork. Clean the internals and lubricate, preferrably with a teflon loaded grease or teflon spray. (Spray is less durable than grease)
This will take care of your steering problems.
Alternatively you can have a look at the Quinny Buzz All Terrain wheels. It's a sturdy drop-in replacement for the original wheel:http://www.babycare.nl/quinny-buzz-all-terrain-voorwiel-p-1819.html
Please contact us through the contact form on our website if you need further assistance.
Erwin de Raad