Rogers Yahoo Mail sync with outlook on new PC, past PST files and iPhone

Hey guys,

Wondering if the community can help me troubleshoot something but first some context:

 -I got a new PC to replace my old one. I use outlook (classic) on my PC and the Mail app on my iphone

-All of my emails on my old laptop were saved to pst files which I have access to

- I had it set up on my old laptop so that outlook permanently saved all of my emails that I sent and received while on my iphone, the Mail app only saved inbox messages that hadn’t been already received to outlook. Once they were received in outlook, they disappeared from the Mail app. Meaning the Mail app was quite light and never had more than a few emails in it (because I have outlook open more than the Mail app etc)

-I am on iOS 18.1.1 on my iphone

On my new PC, I installed outlook classic and installed my Rogers Yahoo mail successfully (so I thought). Now the following is happening:

-On outlook, only a random segment of my inbox past messages are visible

-In the Mail app, it shows all of the above random segment of inbox past messages

-If Outlook is open, it will not received emails. However the Mail app will

-Once I close outlook and reopen it (even if the Mail app is open), whatever emails were received in the Mail app will now be visible in Outlook

-The Mail app can send and receive emails without issue. All emails appear in the Mail inbox regardless of Outlook’s behaviour

My questions:

-How can I revert the Mail app’s behaviour to what it was with my old computer?

-How can I import all of my old pst files to ensure they show up in my laptop outlook and do not crash outlook? (I tried importing once before and I think it screwed up as outlook kept crashing so I deleted my Rogers Yahoo Mail account from Outlook and restarted the process without trying to import pst’s yet)