Unhandled Exception: Instance of 'StripeConfigException'

[GAPangilinan]

ERROR STACK:
E/flutter (30263): [ERROR:flutter/runtime/dart_vm_initializer.cc(41)] Unhandled Exception: Instance of 'StripeConfigException'
E/flutter (30263): #0 Stripe.publishableKey (package:flutter_stripe/src/stripe.dart:30)
E/flutter (30263): #1 Stripe.applySettings (package:flutter_stripe/src/stripe.dart:104)
E/flutter (30263): #2 Stripe._awaitForSettings (package:flutter_stripe/src/stripe.dart:626)
E/flutter (30263): #3 Stripe.initPaymentSheet (package:flutter_stripe/src/stripe.dart:463)

Help I didn't find the solution. I tried double checking the publishable key but its still the same on the backend.