Re: "picsart : accidental purchase, i thought i had 7 days trial".
We are all Apple users, like yourself, in this community, and we have no access to your accounts or details. So we do not have any info. about your purchase. We'd like to help, however.
A free trial generally needs to be cancelled at least 24 hours before it expires, if you do not want to be charged.
If it is a subscription: you may need to cancel that so you are not charged for the next month.
Wondering where you purchased the App from, and who would have your purchase-money.
The best source of help for a product not made by Apple (a third-party product)
is the company or person who made it—its vendor or developer:
How to: Contact a third-party vendor - Apple Support
or
Picsart online:
https://support.picsart.com/hc/en-us/articles/360002231937-Refund-Policy
If you made a purchase from the App Store:
You might want to: Find the URL for an app in the App Store to report a concern - Apple Support
How to: Report a problem: https://reportaproblem.apple.com/?s=6
More info. / support / contact:
App Store support website: App Store - Official Apple Support
or
Billing and Subscriptions support website: Subscriptions and Billing - Official Apple Support