Hi Jason,
As Steven has mentioned, there reason that both of these fields are read-only is because someone has used the Select Reorder Storeroom option in the Storeroom application. When used the applies that storeroom as the Primary Vendor.

You will need to follow Steven's suggestion of removing that value. Of course, that does mean that all items in the store will now have no primary vendor. I would recommend that you follow-up and apply the Primary Vendor then to each item in the store (if known).
Primary vendor
If you define a vendor, you can at any stage select a storeroom to replace the vendor. When you do this the Vendor field becomes read-only and to revert back to the vendor you have to uncheck the Internal? flag. There will be a delay between the operations, but for those of course, I can't wait so I save then complete the change.
Hope that helps.
Regards, Craig
Principal Consutlant, COSOL
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