Troubleshooting lens problem

[Jeviko Liongky]

Dear there,

I noticed some debris and possible cracking in my self-assembly miniscope (picture attached), although I'm not sure which lens that is the problem.

Is there any way to troubleshoot this problem? Can anyone help on how to disassemble the miniscope for cleaning these debris?

If it's not working and the lens do have some cracks, do I need to purchase and replace some of the parts to fix this issue? 

Thanks in advance, looking forward to hearing from you.