Deploy react app on heroku keep showing application error:SyntaxError: Cannot use import statement outside a module“

Here is the log tail .
› Warning: heroku update available from 7.29.0 to 7.39.3.

2020-04-17T16:35:48.096847+00:00 app[web.1]: SyntaxError: Cannot use import statement outside a module

2020-04-17T16:35:48.096847+00:00 app[web.1]: at wrapSafe (internal/modules/cjs/loader.js:1070:16)

2020-04-17T16:35:48.096847+00:00 app[web.1]: at Module._compile (internal/modules/cjs/loader.js:1120:27)

2020-04-17T16:35:48.096848+00:00 app[web.1]: at Object.Module._extensions…js (internal/modules/cjs/loader.js:1176:10)

2020-04-17T16:35:48.096848+00:00 app[web.1]: at Module.load (internal/modules/cjs/loader.js:1000:32)

2020-04-17T16:35:48.096848+00:00 app[web.1]: at Function.Module._load (internal/modules/cjs/loader.js:899:14)

2020-04-17T16:35:48.096848+00:00 app[web.1]: at Function.executeUserEntryPoint [as runMain] (internal/modules/run_main.js:74:12)

2020-04-17T16:35:48.096849+00:00 app[web.1]: at internal/main/run_main_module.js:18:47

2020-04-17T16:35:49.414977+00:00 heroku[router]: at=error code= H10 desc=“App crashed” method= GET path="/" host=boiling-beyond-71113.herokuapp.com request_id=868a12a2-ae4b-4113-88e6-4c1e8fcd2c71 fwd=“24.218.1.91” dyno= connect= service= status=503 bytes= protocol=https

2020-04-17T16:35:51.700159+00:00 heroku[router]: at=error code= H10 desc=“App crashed” method= GET path="/favicon.ico" host=boiling-beyond-71113.herokuapp.com request_id=d65908b4-78fd-4336-8045-6edee73f3f9d fwd=“24.218.1.91” dyno= connect= service= status=503 bytes= protocol=https

2020-04-17T16:42:50.000000+00:00 app[api]: Build succeeded

2020-04-17T16:42:55.353493+00:00 heroku[web.1]: State changed from starting to crashed

2020-04-17T16:42:55.255279+00:00 app[web.1]: /app/src/index.js:1

2020-04-17T16:42:55.255303+00:00 app[web.1]: import React from “react”;

2020-04-17T16:42:55.255304+00:00 app[web.1]: ^^^^^^

2020-04-17T16:42:55.255305+00:00 app[web.1]:

2020-04-17T16:42:55.255305+00:00 app[web.1]: SyntaxError: Cannot use import statement outside a module

2020-04-17T16:42:55.255306+00:00 app[web.1]: at wrapSafe (internal/modules/cjs/loader.js:1070:16)

2020-04-17T16:42:55.255306+00:00 app[web.1]: at Module._compile (internal/modules/cjs/loader.js:1120:27)

2020-04-17T16:42:55.255307+00:00 app[web.1]: at Object.Module._extensions…js (internal/modules/cjs/loader.js:1176:10)

2020-04-17T16:42:55.255307+00:00 app[web.1]: at Module.load (internal/modules/cjs/loader.js:1000:32)

2020-04-17T16:42:55.255307+00:00 app[web.1]: at Function.Module._load (internal/modules/cjs/loader.js:899:14)

if anyone know how to solve it, let me know. Thanks.