Cellphone cannot reach AT&T landline

[att_landline]

Several Verizon Wireless users in 504 area code cannot reach my AT&T landline (area code 504, exchange 367). I've contacted AT&T yet they say it's a Verizon problem. (I am not a Verizon wireless subscriber.) AT&T wrote me that it's probably not a "routing problem", based on the following calling experiment from a user's Verizon Wireless phone to the land line in question, (504)xxx-xx90, i.e. some phone numbers work fine, others seem to be not connected - but mine, xx90 has a unique "cannot be completed" message:

Also: This same AT&T landline *can* reach the Verizon Wireless phones tested, and AT&T and T-Mobile cellphones can reach this AT&T landline.

This is what a cellphone on the Verizon Wireless network gets when calling the xx90 landline and nearby numbers in the same exchange:

xxx-xx80 ringing ("hello - please leave a message after the tone")
xxx-xx81 ringing - apparently a fax machine (typical fax beeps and static...)
xxx-xx82 We're sorry, you have reached a number that has been disconnected or no longer in service.
xxx-xx83 We're sorry, you have reached a number that has been disconnected or no longer in service.
xxx-xx84 We're sorry, you have reached a number that has been disconnected or no longer in service.
xxx-xx85 We're sorry, you have reached a number that has been disconnected or no longer in service.
xxx-xx90: Your call cannot be completed as dialed. Please check the number...
xxx-xx91: We're sorry, you have reached a number that is disconnected or no longer in service.
xxx-xx92: We're sorry, you have reached a number that is disconnected or no longer in service.

How can this problem be solved?

[LawrenceC]

These forums are dedicated to Residential products and services offered by Verizon.

For help with Verizon Wireless issues, please post your topic on the Verizon Wireless community.

Thank you.