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Well-known member
Aug 20, 2015
Manning, SC
I seem to be having a problem with my sim on a Nighthawk M6 device and plan to find an AT&T store along our travels the next two weeks. I am getting a regular error of No Sim and have to open the unit and move the sim around until it works again. Here is my concern. This plan has not been offered for years and since it is a truly and unlimited plan for $20.00 a month I don't want to do anything to mess things up. Is there any way the just replacing the sim can affect the ultimate use of the grandfathered plan? Can the reps change or remove me from the plan while in the process of replacing the sim. Has anyone else had to replace the sim and was there any problems? Sorry for sounding a little paranoid, but I am. There is nothing like this out there and I don't want to loose it. We use it a lot while on the road. Chuck
Yes the reps can "upgrade" you to a more expensive plan, and once its gone there is no way to get the CCU plan back. If you go get a new SIM be VERY clear with the REP that you DO NOT want them to make ANY changes to your plan.
An AT&T store rep replaced my Connected Car SIM a couple of years ago with no problems and no plan changes. He did briefly try to upsell me on a newer hotspot, but didn't really push it.
No, it's the sim, I'm sure. Thanks for the other input. This is my big concern. Bill, Can you explain to me just what happened to change your plan? Chuck
It happened several years ago when in Minnesota on vacation.

I think I got water in the phone and had to replace it with a phone of the same model.

After leaving, I discovered that my "Grandfathered Unlimited Plan", was replaced with a newer plan that was not unlimited.

I was very surprised that I could not get them to reverse the change.

I changed providers over it.

Thru the years my monthly bill had grown by adding new phones, devices, and relatives, (Sons), on the bill and my monthly bill is about $400 a month.

If the original provider had not reacted as they did they would still have an almost $5,000 a year customer.
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That's a bummer and the kind of thing I'm concerned about. Since we are just replacing the sim, I can only hope it goes smoothly. I plan to let them know in no uncertain terms not to change anything. Chuck
My mistake was in not carefully monitoring what they had me sign when I got the phone.

Knowing upfront what they are doing for you should make you prepared to catch any attempt at changing your plan.
The problem might be a bad connection. There is a produce you can find at Micro Center and selected other Electronic/tech stores DE-OX-IT and a 2nd De-Ox-It Sheeld

De-ox-it comes in assorted numbers 5-100 (5% to 100% strength) Use De-OX-It xx first
then the shield on both the sim card and teh socket. wait a bit between shots.
I use De-Ox-It on all my electrical connections. I will give it a try but doubt this is the problem. I have cleaned the contacts and sim with a pencil eraser and contact cleaner but it didn't help. Chuck
While traveling out of town recently replaced att 5g sim for nighthawk m6 with no problem. moving sim back and forth from camper router & nighthawk bunged a corner of the sim. Also just replaced att sim for legacy unlimited lte plan with no problem.l, no change to plan. Very smooth process.
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