清单合并失败并出现多个错误，请参阅日志（PayUMoney 集成）

我正在尝试在我的应用程序中集成 PayUMoney 支付网关。集成文档的第一行说要添加 -

compile 'com.payumoney.sdkui:plug-n-play:1.0.0'

在我的应用程序级 build.gradle 文件依赖项中。但是一旦我这样做，我就会遇到一个错误 -

清单合并失败并出现多个错误，请参阅日志也行 -

执行 'com.android.support:appcompat-v7:26.1.0'

显示以下错误 -

All com.android.support libraries must use the exact same version specification (mixing versions can lead to runtime crashes). Found versions 26.1.0, 23.2.1. Examples include com.android.support:animated-vector-drawable:26.1.0 and com.android.support:cardview-v7:23.2.1 less... (Ctrl+F1) 
There are some combinations of libraries, or tools and libraries, that are incompatible, or can lead to bugs. One such incompatibility is compiling with a version of the Android support libraries that is not the latest version (or in particular, a version lower than your targetSdkVersion.)

帮我解决这个问题。

下面是我的 build.gradle(Module:app) 代码-

apply plugin: 'com.android.application'

android {
    compileSdkVersion 26
    defaultConfig {
        applicationId "com.learnturtle.payucheck"
        minSdkVersion 15
        targetSdkVersion 26
        versionCode 1
        versionName "1.0"
        testInstrumentationRunner "android.support.test.runner.AndroidJUnitRunner"
    }
    buildTypes {
        release {
            minifyEnabled false
            proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
        }
    }
}



dependencies {
    implementation fileTree(dir: 'libs', include: ['*.jar'])
    implementation 'com.android.support:appcompat-v7:26.1.0'
    implementation 'com.android.support.constraint:constraint-layout:1.0.2'
    testImplementation 'junit:junit:4.12'
    androidTestImplementation 'com.android.support.test:runner:1.0.1'
    androidTestImplementation 'com.android.support.test.espresso:espresso-core:3.0.1'

    compile 'com.payumoney.sdkui:plug-n-play:1.0.0'
}