If you are using a superhub, then simply do a pin-hole reset, which will reset the superhub to default.
Login details will be: admin / changeme. You can then choose a new wifi password. dozer167
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As previously asked, which model of router do you have? If you can login to the router then you may be able to obtain or reset the password from there.
Also, do you have any PC's which connect wirelessly? If so, you may be able to go into your wireless network settings and show the characters in your passphrase, negating the need to even touch the router.