Azure Functions 2.x runtime is based on .NET Core 2 from .NET Framework 4.7 in 1.x. So, any application migrating from 1.x to 2.x needs to make sure that they are using and referring the compatible code and libraries.
We can also update our Azure Functions to target the appropriate runtime using the below steps à
Inside Azure Portal, select the Function App, click on Application Settings within Platform Features tab.

We can specify the version number for the APP SETTING NAME – FUNCTIONS_EXTENSION_VERSION
~ tilde à indicates that the latest version of that major version.

Get all the details here
https://docs.microsoft.com/en-us/azure/azure-functions/functions-versions
Hope it helps..









We have run into many scenarios where a company has Office 365 and then orders Dynamic 365 from a CSP (Cloud Service Provider) and their systems end up different tenants. As Microsoft moves to the model where there can be more than one partner of record and various flavors of Dynamics 365 (Finance and Operations, Business Central, Customer Engagement, etc..), I can see this problem getting more prevalent over time.