Please correct me if any of these sentecnes are wrong

Hello,

Please correct me, if any of these sentecnes are wrong.

  1. I was calling you, but it was going to voice mail this morning.

  2. I was trying to reach you, but it was going to voice mail this morning.

  3. I could not reach you this morning, because it’s going to voice mail.

  4. As I was unable to reach you this morning, I left a voice message for you.

Thanks for your help,
Sagar

1-2) They’re okay - I’d prefer ‘it kept going to voice mail’.
3) could not and it is don’t combine well. Again, I would use ‘it kept going to voice mail’ (even if it is still morning!)
4 is fine.

Thank you Beeesnees.