Router not working after changing

[Sarahdng]

Hello, I changed internet plan and Sky has sent a new router. 
I've been asked to send the old router back. 
main thing is that internet doesn't work with new router whilst working with old one. 

Should I keep the old router and send back the new one? I don't want to be charged £67. 

thanks 

[caesarome]

@Sarahdng 

Were you upgrading to Sky fibre ?

Either way if you have a new router it will have a new wifi password so have you set up all your devices again using the new Wifi name and password. Either that or login to the new router and change the name and password to the same that your old one was using.

[Sarahdng]

Just upgraded speed from 300 to 500 but still fibre. 

but how come my old router is now working while the new One is not working?