Joolz Geo2 unusual frame noises (creaking/clicking/squeaking )

The key things to check with unusual noises coming from your stroller are:

Wheels pins and axels

As part of regularly maintenance lubricate wheel pins with a grease lubricant (petroleum jelly/Vaseline) and apply a spray lubricant (WD40/Silicone spray/lube rice etc) around the front wheel axel. 

Brake mechanism

Remove rear wheels and check brake pins fully retract when brake is not engaged by applying and releasing brake by hand and checking the movement of the brake pin is equal on both sides. If the brake pin doesn't fully retract ensure this area is clear from dirt/grit/debris and apply a spray lubricant (WD40/Silicone spray/lube rice etc) 

Leave the stroller tipped on it's side to allow the lubricant to soak around the brake pin and leave for a couple of hours. 

 
Fold Mechanism

Where the stroller folds at the front of the frame/chassis is the most likely source of unusual creaking or squeaking noises. Especially if these noises occur when the stroller isn't in motion, but just rocking the frame back and forth. 

To resolve this issue the first thing to try is check the screws found on either side of the front of the fold mechanism are tight - and tighten if these have become loose. 

Check the area around the joint is free from any dirt/grit/debris and then apply a spray lubricant (WD40/Silicone spray/lube rice etc) liberally around the moving parts of the fold joint. (Circled below)

Fold and open the stroller a few times to work the lubricant around the moving parts and then leave the stroller for a few hours before testing if this resolved the issue.