I`m currently using Zoho email through Gmail. I follow all the guidelines supplied by Zoho on the setup and it worked perfectly until yesterday.

I got blocked:  554 5.1.8 Sender Address Blocked

I don't know the reason once I sent only around 10 emails. This is my main tool for work and I'm currently blocked to operate on a daily basis. Is there any way I can speed the unblocking process up?

Moreover, how to avoid the same to happen again? Working on sales is natural to get the wrong email address and send a lot of daily emails.

Additionally, a lot of my prospects informed that Zoho email (my email) always get into the spam folder. Which does not happen from my Gmail account. Anything to fix here?

Best,

LC