How can use a stable coin with a smart contract on Polygon

Question

I'm working on a smart contract that allows users to pay for monthly subscriptions depending on the plans that they choose. I deployed the smart contract on Polygon mainnet using remix IDE. when I created the plan using createPlan function with USDT/Polygon, then I triggered the function subscribe to pay subscription using USDT (https://polygonscan.com/token/0xc2132d05d31c914a87c6611c10748aeb04b58e8f) That I have in my wallet I got this error message :

pragma solidity ^0.8.10;
import '@openzeppelin/contracts/token/ERC20/IERC20.sol';
contract Payment {
  uint public nextPlanId;
  struct Plan {
    address merchant;
    address token;
    uint amount;
    uint frequency;
  }
  struct Subscription {
    address subscriber;
    uint start;
    uint nextPayment;
  }
  mapping(uint => Plan) public plans;
  mapping(address => mapping(uint => Subscription)) public subscriptions;
event PlanCreated(
    address merchant,
    uint planId,
    uint date
  );
  event SubscriptionCreated(
    address subscriber,
    uint planId,
    uint date
  );
  event SubscriptionCancelled(
    address subscriber,
    uint planId,
    uint date
  );
  event PaymentSent(
    address from,
    address to,
    uint amount,
    uint planId,
    uint date
  );
function createPlan(address token, uint amount, uint frequency) external {
    require(token != address(0), 'address cannot be null address');
    require(amount > 0, 'amount needs to be > 0');
    require(frequency > 0, 'frequency needs to be > 0');
    plans[nextPlanId] = Plan(
      msg.sender, 
      token,
      amount, 
      frequency
    );
    nextPlanId++;
  }
function subscribe(uint planId) external {
    IERC20 token = IERC20(plans[planId].token);
    Plan storage plan = plans[planId];
    require(plan.merchant != address(0), 'this plan does not exist');
    token.approve(address(this), plan.amount); 
    token.transferFrom(msg.sender, plan.merchant, plan.amount);

    emit PaymentSent(
      msg.sender, 
      plan.merchant, 
      plan.amount, 
      planId, 
      block.timestamp
    );
subscriptions[msg.sender][planId] = Subscription(
  msg.sender, 
  block.timestamp, 
  block.timestamp + plan.frequency
);
emit SubscriptionCreated(msg.sender, planId, block.timestamp);

}

How can solve this? Am I using the wrong USDT address? Thank you