Hi,
You don’t state the make or model of the blinds or what the actual problem is.
There are plenty of videos on YouTube that show how to repair cordless blinds.
Here are some examples:
https://www.youtube.com/watch?v=yNUNbWibDs4
https://www.youtube.com/watch?v=Cugy33wHltI
https://www.youtube.com/watch?v=AIX1GxpHFlU
https://www.youtube.com/watch?v=O86RYtR0-XA
If you wish to create make a repair guide for your particular blinds as you are repairing them and would like to post it on ifixit for the benefit of others in the future, here’s how to do this. [guide|102668]