Why am I having wifi authentication problems?

[AC Question]

I just bought a brand new Huawei G650 or Huawei G Play mini (I'm not sure what the official name of it is), and as I got home, I tried to connect to my wifi. After several tries and using several different codes I got from the stickers under the router, I went and checked the correct password on my computer and I am 100% sure I used the right one, correctly typed. However, when I do insert it, and appears as "saved" but no connection, and as I touch "connect", it always says I have the wrong password. What can I do to fix this, please? Thank you for your time.