Hi shaneela145,
Welcome to the Apple Community
Re: Is there any issue in apple subscriptions?
Not that I know of.
Apple is very protective of the finances and security of those who use it's products and services.
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Re: "updated my payment option and it isn’t working"
You may need to ask your financial institution (ie your credit / debit card provider)
to ensure that your card can be used for international payments.
Also: Sometimes local laws may be prohibiting to payment or financial arrangements.
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Re: "I want to buy iCloud but my payment is declined"
We are all Apple users, like yourself, in this Community.
We have no access to your accounts or details to check this out for you.
We'd like to help, however.
Seems you need a payment method Apple can accept in the same country as listed in your Apple ID account.
Payment methods that you can use with your Apple ID – Apple Support
says:
Pakistan
Most credit and debit cards
or
Apple ID balance (from adding funds)
You can check if your payment method details are correct in your Apple ID account online:
Apple ID Log-in https://appleid.apple.com
or
How to: Change, add, or remove Apple ID payment methods - Apple Support
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If needed:
What you can buy with your Apple Account Balance
How to: Check your Apple Account balance – Apple Support
How to Add money to your Apple Account balance - Apple Support
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As the "Related article" above your question:
If your payment method is declined in the App Store or iTunes Store - Apple Support
says:
If you still need help, contact Apple Support.
Apple phone numbers around the world
Contact Apple for support and service - Apple Support
says:
Pakistan
Dial 00800 01001 first,
then dial 800 361 0479
Local and national telephone rates apply
Toll-free phone number is for landlines.
You may be charged when calling from a mobile phone. This number may not be accessible from some mobile network providers. For more information, contact your network provider.
All the best :-)