Ionic project not building for android

Hello all, please i need some help. I am unable to build and generate apk files for my ionic projects. it started about two weeks back, i have tried all i can including uninstalling cordova and android sdk and re-installing them back but to no avail.

The error am getting for why the build cannot be completed is as follows:

" Execution failed for task ‘:transformClassesWithDexForDebug’. "

Please, i would appreciate if someone could help me out of this issue.

Below also is the image of the build error: