Square Reader Not Connecting

Questions
1

I have implemented the Flutter plugin for the Square Mobile Payment SDK and am currently using the production App ID. While attempting to connect the Square Reader through the Square settings screen, I receive a “Reader pairing successful” message; however, it is followed by the error:

“Reader unavailable: Unable to establish a secure connection to Square.”

From my end, I have already:

  • Updated the app signature (SHA-256) on the Square Dashboard

  • Activated the Square account

Could you please confirm if any additional setup or configuration is required to resolve this issue?

2

Do you mind providing me with the following?

  • Your application ID (not your access token)

  • The Location ID you’re having issues with

  • A timestamp of one example of this issue occurring (date, time, timezone)

3

my app id: sq0idp-QfPisfD-yzpV-RK2AyZwtw

location id: LVTQNWPT4YY0N

Error: Reader Unavailable, Unable to establish a secure connection to Square

Timestamp: 1:20 pm, 01/05/2026, Canadian Timezone

4

@Shubham2502 Can you also share the Mobile Payments SDK version you’re using?

5

Flutter SDK Version:

square_mobile_payments_sdk: ^2026.3.1

app/build.gradle

dependencies {
    implementation("com.squareup.sdk:mobile-payments-sdk:2.4.0")
}

let me know if you need any additional details

6

@Shubham2502 It looks like you’re testing your Flutter application on Android when this issue is occurring, is that correct? If so, does the issue seem limited to Android, or does it also occur on iOS?

7

Yes I am testing on Android, i will not be publishing app on app store.

8

@Shubham2502 We’re having some trouble tracking down the logs for this. Can you confirm which Canadian timezone your timestamp was for?

Timestamp: 1:20 pm, 01/05/2026, Canadian Timezone

9

Toronto Timezone GMT - 4:00

10

Thanks @Shubham2502. We weren’t able to find anything in the logs that indicate any unusual errors here. Can you try the following to troubleshoot?

  1. Try to get the app signature from an APK.

  2. Make sure that app signature matches what’s in your developer console.

  3. Try to install that APK and see if your error still persists

11

no luck, i am using the correct SHA-256 release key which i used while building the apk

i also tried with debug key but same issue