Before you install the package, you need to configure certain things in Salesforce settings to prepare the environment for PosiPay.
Person Account Activation
Note: Do this before installing a new package.
Reference: Enabling Person Accounts in Salesforce
Assign the Person Account record type correctly in the Account Object.
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Enable Lightning Web Security (LWS)
If you are using an older Salesforce org, it is important to activate Lightning Web Security to ensure that the Stripe library functions properly on your org.
Go to Set up > Home page > Search for Session Settings > Tick Lightning Web Security
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Next place to go : Step 2 - Installation