What make/model phone do you have? On my Droid Turbo 2, in Message+ v6.6.4 Settings->Notifications, I have a 'Notifications During Call' option to Enable or have Disabled.
POPPAWOOD, we always value your feedback so we can help make the right changes with our upcoming software updates. At this very moment, there's no news regarding this feature on the 6.6.4 version of the Verizon Messages or Message+ application. You may reach out to the developers directly at "VerizonMessage@VerizonWireless.com" to get more information.
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