imaginarymusiclover, we want to welcome you to the Verizon Family! We understand the importance of making sure you are able to select the right plan for your usage needs. Allow us the opportunity to further review the details of your concern. Can you please clarify if you have already activated your device and selected the 2GB data plan? If you have already selected the 2GB plan, you will be able to change your plan to the unlimited $75.00 plan and will only be charged for the plan difference. Please follow this link for more details https://vz.to/2HB8Mz4 and reference number 4 from the “Managing Your Prepaid Account” section.
If you have not activated your device yet, when you activate your device you will definitely be able to select the plan of your choice. Although you have purchased a $40.00 prepaid card, you can simply apply the $40.00 to your account and pay the difference of the $75.00 plan. Does this information help? Here is a helpful links on how to process your payment online https://vz.to/2I0ya4O .
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