Hi!
I've just created a completely new Atlassian site for a new startup company. I opened Jira and created a new Space. Everything works fine up to this point. When I try to connect a Bitbucket repository, it navigates me to the "DVCS Accounts" page. I press "Link Bitbucket Cloud workspace" and get this error:

When I try to connect it from the Bitbucket side instead (Workspace settings → Atlassian integrations → Jira), it throws this error: "Unable to connect. A Jira admin needs to remove the connection in Jira before you can connect via Bitbucket." But nothing shows up under DVCS Accounts in Jira to remove.
Also, under Jira Space settings → Apps, I usually see 'Microsoft Teams Integration' and 'Slack integration' listed as available apps on my other (slightly older) sites. These two are completely missing on this new site. See screenshot:

I already tried resetting the site by creating a second empty site, backing it up, and restoring that backup onto this broken site; hoping it would wipe and fix the app configuration. This did not resolve the issue.
It feels like something went wrong during site provisioning, like some default app installations never registered. Does anyone have suggestions on how to fix this? I really would like to keep my site's (sub)domain.
Thanks in advance!