Trying to exploit SQL injection

Question

I am trying to exploit a SQLI and I don't understand why my "group_concat" doesn't work.

I managed to extract the name of the database ("games") :

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But when I try to extract the tables from this database, I have a syntax error : enter image description here

Why do I have this syntax error?

PS: This is being done on an hacking learning plateform so no nasty illegal stuff going on.