Use the configured signer, not the provider's

src/base/vesting/vesting.ts

@@ -3,7 +3,7 @@ import { formatBalance } from "@app/utils";
 import * as session from "@app/session";
 import { State, state } from "./state";
 import type { Config } from "@app/config";
-
+import { assert } from "@app/error";
 
 export interface VestingInfo {
   token: string;
@@ -15,8 +15,10 @@ export interface VestingInfo {
 }
 
 export async function withdrawVested(address: string, config: Config): Promise<void> {
+  assert(config.signer);
+
   const contract = new ethers.Contract(address, config.abi.vesting, config.provider);
-  const signer = config.provider.getSigner();
+  const signer = config.signer;
 
   state.set(State.WithdrawingSign);
 

src/session.ts

@@ -48,6 +48,7 @@ export const loadState = (initial: State): Store => {
   return {
     subscribe: store.subscribe,
     connect: async (config: Config) => {
+      assert(config.signer);
       const state = get(store);
 
       assertEq(state.connection, Connection.Disconnected);
@@ -60,7 +61,7 @@ export const loadState = (initial: State): Store => {
         console.error(e);
       }
 
-      const signer = config.provider.getSigner();
+      const signer = config.signer;
       const address = await signer.getAddress();
 
       try {
@@ -208,7 +209,9 @@ state.subscribe(s => {
 });
 
 export async function approveSpender(spender: string, amount: BigNumber, config: Config): Promise<void> {
-  const signer = config.provider.getSigner();
+  assert(config.signer);
+
+  const signer = config.signer;
   const addr = await signer.getAddress();
 
   const allowance = await config.token.allowance(addr, spender);