3rd 2ch - what does it mean?

[Shahr]

Can you please explain what they mean by slip stitch join into 3rd 2ch. I do not understand the 3rd 2ch part. 
Thanks!!

[Granny Square]

That's an odd one.  Are you working in DC in the round, and does it make sense for you to be joining the last DC to the first DC, which is turning chain of 3 chains?  In that case I'd consider the 2 a typo. 

The only thing that I can think of that would make sense is if you were making something lacy, and there were multiple chain-2 loops ahead of you, and you were to join in the third of these loops.  But the wording is weird, unless English isn't the designer's first language perhaps.

[Shahr]

Yes I am working in a hexagonal shape and am working in double crochets (US terminology). Here are the instructions. I will try to attach a photo. 

[Granny Square]

I would use my best judgement on where the round should end (somewhere in the corner loop), and what makes sense with the initial instruction in the next round (which isn't always the same); I see it's not a typo as it occurs at the end of several rounds. 

I've never seen an instruction worded that way, it's not clear at all.  Sorry I can't be more helpful.

[Shahr]

Thanks so much for trying!!!