'was' or 'have been' : Which one should I use in the following sentences?

1- I was/have been happy with the job until now.

2- I was/have been a teacher until now.

3- I was/have been facing a hard time in my life until now.

4- I didn't face/haven't faced any problems until nownow with the project.

Hi everyone, will there be any difference in meaning if past tense and the perfect tense are used interchangeably in these cases?