Solved: "Renew" / payment option not showing for an expired Developer Program membership (region + wrong Apple ID mismatch)
Posting this in case it helps someone, because I spent over an hour on the phone with support and ended up fixing it myself.
My situation
The Developer Program membership had expired and I could not renew it. There was no Renew button and no payment option anywhere on the developer website — the web checkout simply would not process a renewal. The Apple Developer app didn't show a renew option either.
The reason turned out to be a combination of two things:
The membership was originally purchased with a different Apple ID than the one tied to the developer account. Our developer account is under a company Apple ID, but the original $99 purchase had been made years ago through a personal Apple ID. The subscription "lives" under whichever Apple ID actually paid for it — not necessarily the one you log into the developer site with.
The App Store region didn't match the region of the original purchase. At some point I had set that personal Apple ID's App Store region to the US, but the original Developer Program purchase had been made in the Turkey store. Because the store region didn't match, the expired/cancelled Developer subscription wasn't visible in Subscriptions at all — so there was nothing to renew.
What actually fixed it
On the iPhone, I signed in with the Apple ID that originally made the purchase (not the developer-account login email).
I switched that Apple ID's App Store region back to the country where the original purchase was made (in my case Turkey).
Once the region matched, the Apple Developer subscription appeared in App Store → Subscriptions again.
I then opened the Apple Developer app, signed in, and the Renew option finally showed up. Renewal went through immediately as a normal App Store purchase.
Key takeaways if you're stuck with no renew/payment option:
The renewal lives under the Apple ID that paid, which may not be your developer-account login.
Your App Store region must match the region of the original purchase, or the subscription won't even show up.
The iPhone (Settings → Subscriptions, or the Apple Developer app) route works when the website refuses to renew.
Hope this saves someone the hour I lost.