Is there a way to request a phone be whitelisted?

No. 

That's up to the manufacturer. 

The manufacturer has to have the phone tested to show that it can work with AT&T service especially voice services. If the manufacturer didn't, or won't, then none of those model phones are whitelisted for AT&T

Ok so the phone in question is fairly new and the rest of the phones made by this manufacturer are listed on the white list. the phone is 4g and sold in the USA. Would it be a case of the white list just isn't up to date? I just don't want to buy this phone and then not be able to use it. 

But you don't say what phone... 

? 

The white list is essentially useless as it's not been updated since summer of 2022.  

You would be taking your chances. Make sure you can return the phone.  

Check imei (not that it's a garentee 

https://www.att.com/buy/byod/identify?devicetype=phone

Yea I was trying to keep it generic but the phone is the CAT S22 flip. I have seen people  able to use it with prepaid sims... but I'm not alone on my plan so that is probably not a good route

It has no effect on anyone else if you byod.  And IMEI are printed on the box. So you can check the IMEI before you even take the phone home.  

The worst that can happen is you switch your sim card into the phone and the phone won't make phone calls, which means you mean you have to switch the SIM card back into a functioning phone.

If buying from best buy, they should know if a phone is compatible. 

The worst that can happen is you switch your sim card into the phone and the phone won't make phone calls, which means you mean you have to switch the SIM card back into a functioning phone.

Actually, that's not the worst that can happen. I remember a while back I put an AT&T SIM into an incompatible phone and they just flat out disabled the SIM. Had to jump through some hoops to get it re-enabled. Not sure if they still do that or not, but I'd think twice before trying it again unless I was right in front of an AT&T store :)

They aren't suspending the lines anymore. If your phone doesn't work that's kind of the customers problem now.  

They aren't suspending the lines anymore. If your phone doesn't work that's kind of the customers problem now.  

That's good to know. I'll feel better now about moving the SIM between phones. IMHO they should have never been so aggressive as to suspend, an SMS with info would have been good enough.