Call settings

I doubt it is your phone. I have the same issue. I have a ZTE Grand X and have the same two options under "Additional settings" both are greyed out. So are my call forwarding options. However, this is intermittent. Because I have to turn off call waiting for my job, I have talked to cricket support and searched online regarding this error in these two setting screens as well as the fact that they are greyed out. Here's what I found online: Almost all android phones on all carriers have this issue. I have also discovered that it's completely impossible to actually disable call waiting entirely from any cell phone or landline for any amount of time. What is supposed to happen is that on cell phones you should be able to disable the "call waiting notification". This directs the calls to the numbers in your call forwarding menu. If that menu is greyed out as well ( mine is now but wasn't before I called Cricket customer service) then the numbers entered in the call forwarding options (busy, unreachable, etc) will default to the number programmed in. If they are not greyed out you should see your voicemail number under each option. It is apparently impossible to change that call forwarding number. Before they were greyed out I got an error message that didn't allow me to change or delete the forwarded number.

I think what's happening with you is that your call forwarding options were not automatically loaded with your voicemail number but, instead, each call forwarding option was turned off. This would cause a busy signal if you are on the phone. 

So, end result: call cricket tech support or use their chat service online to talk to a rep. Tell them your call forwarding is greyed out and you cannot access it to enter the voicemail number. They should be able to fix this on their end. As for the call waiting being greyed out with the network error, it's not cricket, it's not your phone, it's many Android OS on many phones. Because I do not have an iPhone I didn't specifically check to see if iPhones had the same issue but it wouldn't surprise me. It's a widespread bug. It's important to note that when I chatted with cricket customer service they were able to do something on their end which made the additional settings not greyed out anymore. This allowed me to change the setting but as soon as I rebooted my phone the areas were greyed out again and the settings I chose did not stick. So, I have an appointment with advanced tech support tomorrow. Given the information I found out today online about how widespread this issue is, I don't think they'll be able to fix it. I bet they can fix your call forwarding options on their end though. That should, in theory, get rid of the busy signal. I hope this helps. It's not encouraging but you aren't alone. If you have discovered a fix since July, please let us know The really messed up problem is that I can't access these settings to turn them off. I would LOVE to have your issue and have callers get a busy signal when I'm on the line. If we could trade issues I'd do it in a heartbeat.

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@SA_Graver wrote:

I have a Motorola MotoE5 Cruise. When I go into phone settings/calls/additional settings the Caller ID option says 'Loading settings' and the Call Waiting option will not allow me to turn it on. Both options are greyed out on this screen. Eventually a popup appears that says 'Call settings error. Network or SIM card error (I assume this is it timing out while trying to load the Caller ID settings). People are telling me they are getting busy signal when I am on the phone and they try to call me and the only calls coming in that are ID'ed are from people I have in my contacts. How do I solve these two problems?

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