I can’t pay my bill

I tried paying my bill on the website, but I kept getting an error message and so I tried the quick pay website to pay my bill without signing in but that also wasn’t available. I also tried the app, but I kept getting a message saying that I’m already signed in but I can’t access it right now, because I have to be a customer. I also tried calling, but due to security reasons, it said I can only pay online. Please fix these error so I I can pay my bill soon please reach back soon. Thank you.