Error:

In PackageDiscoveryTrait.php line 383:

  Could not find a matching version of package paytm/pg. Check the package spelling, your version constraint and that the package is available in a stabil  
  ity which matches your minimum-stability (stable).


require [--dev] [--dry-run] [--prefer-source] [--prefer-dist] [--prefer-install PREFER-INSTALL] [--fixed] [--no-suggest] [--no-progress] [--no-update] [--no-install] [--no-audit] [--audit-format AUDIT-FORMAT] [--update-no-dev] [-w|--update-with-dependencies] [-W|--update-with-all-dependencies] [--with-dependencies] [--with-all-dependencies] [--ignore-platform-req IGNORE-PLATFORM-REQ] [--ignore-platform-reqs] [--prefer-stable] [--prefer-lowest] [-m|--minimal-changes] [--sort-packages] [-o|--optimize-autoloader] [-a|--classmap-authoritative] [--apcu-autoloader] [--apcu-autoloader-prefix APCU-AUTOLOADER-PREFIX] [--] [<packages>...]

Solution:

Use a working Laravel-compatible Paytm package

A working and maintained one is:

👉 anandsiddharth/laravel-paytm-wallet

Then publish the config:

php artisan vendor:publish --provider="Anand\LaravelPaytmWallet\PaytmWalletServiceProvider"

Then configure in .env:

PAYTM_MERCHANT_ID=YOUR_MID
PAYTM_MERCHANT_KEY=YOUR_KEY
PAYTM_ENVIRONMENT=PROD
PAYTM_MERCHANT_WEBSITE=DEFAULT
PAYTM_CHANNEL=WEB
PAYTM_INDUSTRY_TYPE=Retail

This is a complete wrapper for Paytm Wallet.