diff --git a/templates/portal_invoice_detail.html b/templates/portal_invoice_detail.html
index 2191a1d..3d885a8 100644
--- a/templates/portal_invoice_detail.html
+++ b/templates/portal_invoice_detail.html
@@ -568,22 +568,48 @@ Reference: ${invoiceRef}`;
 
                 if (statusEl) statusEl.textContent = "Submitting transaction hash to portal…";
 
-                const resp = await fetch(`/portal/invoice/${invoiceId}/submit-crypto-tx`, {
-                    method: "POST",
-                    headers: { "Content-Type": "application/json" },
-                    body: JSON.stringify({
-                        payment_id: paymentId,
-                        asset: asset,
-                        tx_hash: txHash
-                    })
-                });
-
-                const data = await resp.json();
-                if (!resp.ok || !data.ok) {
-                    throw new Error((data && (data.detail || data.error)) || "Portal rejected tx hash");
+                async function submitTxHashWithRetry() {
+                    const maxAttempts = 12;   // about 60 seconds total
+                    const waitMs = 5000;
+
+                    for (let attempt = 1; attempt <= maxAttempts; attempt++) {
+                        if (statusEl) {
+                            statusEl.textContent = `Checking RPC for transaction… attempt ${attempt}/${maxAttempts}`;
+                        }
+
+                        const resp = await fetch(`/portal/invoice/${invoiceId}/submit-crypto-tx`, {
+                            method: "POST",
+                            headers: { "Content-Type": "application/json" },
+                            body: JSON.stringify({
+                                payment_id: paymentId,
+                                asset: asset,
+                                tx_hash: txHash
+                            })
+                        });
+
+                        const data = await resp.json();
+
+                        if (resp.ok && data.ok) {
+                            window.location.href = data.redirect_url;
+                            return;
+                        }
+
+                        const detail = String((data && (data.detail || data.error)) || "");
+                        const retryable = detail.toLowerCase().includes("not found on rpc");
+
+                        if (!retryable || attempt === maxAttempts) {
+                            throw new Error(detail || "Portal rejected tx hash");
+                        }
+
+                        if (statusEl) {
+                            statusEl.textContent = `Transaction sent. Waiting for RPC to see it… retrying in ${Math.floor(waitMs / 1000)}s`;
+                        }
+
+                        await new Promise(resolve => setTimeout(resolve, waitMs));
+                    }
                 }
 
-                window.location.href = data.redirect_url;
+                await submitTxHashWithRetry();
             } catch (err) {
                 if (statusEl) statusEl.textContent = String(err.message || err);
                 walletButton.disabled = false;