This means (as stated in the message) that there are too many connections from your host. Since you state that you are connecting via wifi, there may be other people connecting via that same wifi, and they are sharing the same host address as both of the computers that you are trying to use.
Is this your personal wifi connection (ie: do you have access to change settings and passwords on the wifi)?
If so, I suggest that you change whatever password is currently set to restrict access to the wifi router, and if there isn't one, establish one.
This will reduce or eliminate the number of people that can be using your wifi without your knowledge.

As I don't use wifi, I can't be of any further assistance regarding setting/changing passwords.