ios – PollingbackTracker Error Occures on my iphone when I attempt to ship the transaction by metamask pockets

Lately I am constructing the webapp which may ship the transaction by my very own good contract. And it actually work nicely on Desktop and Android however solely on iphone pollingbackTracker error is occured and the transaction does not return the consequence.

I’ve tried altering the rpc url and it does not work too.
I do not know what’s flawed with it.

pockets : metamask,
community : mumbai (polygon)

...

const web3Modal = new Web3Modal({
    cacheProvider : true,
    providerOptions : choices
});

//join account
const occasion = await web3Modal.join();


const supplier = new ethers.suppliers.Web3Provider(occasion);
const signer = supplier.getSigner();
const contractAddr = new ethers.Contract(addr, abi, signer);

//my contract
//open metamask pockets and ship transaction -> it really works
//however the transaction is not return the consequence
contractAddr.purchase().then(res => console.log(res));