Cannot Update App from PlayStore : Error -504

I have published my app on Google Play. If install its works fine, but not able to update app , I get the same error code, error 504.

Error -504 while installing com.xxxx.xxx: INSTALL_FAILED_UID_CHANGED: Package couldn't be installed in /data/app/com.xxxx.xxx

for logs : E/installd: Couldn't opendir /data/app/vmdl15380*****.tmp: No such file or directory

new version /data/app/vmdl15380*****.tmp/lib/arm/libmain.so: crc = f43565f4, zipCrc = 4097140212

old version: /data/app/com.xxxx.xxx/lib/arm/libmain.so: crc = 83fdc919, zipCrc = 2214447385

Upgraded unity vesion 2017.4.35f1 to 2019.4.12f1 I used gradle setup for project - mainTemplate.gradle

After upgrade made changes to apply plugin: 'com.android.applicaiton' to

apply plugin: 'com.android.library' and removed applicationId 'com.xxxx.xxx'

May be this cause issue ? Any idea ?

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