AdminEmil - I hope you didn't spend too much time looking honestly, because there is no option or process, currently defined**, to merge accounts. 😉 And...fwiw, I'm glad you reached out here; good ideas should see the light of day.
We have never specified a permanent account-merge feature because of the combination of complexity involved and need - not many have asked for, or defined a clear need for, such a feature.
In your case - what are you thinking about? Or what problem are you having/foreseeing that would lead you to want to merge your accounts?
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**There was a short span (about 2+ years) where we maintained a merge function but that was due to a data migration choice we made when we upgraded our platform in 2019. (pre-2019 accounts could be merged with post 2019 accounts for the next 30+ months).