Am I able to merge two Apple ID accounts?

Hi, I have two separate Apple accounts… one for purchases & the other for my cell.

The issue is my (purchases) account email may soon be transferred.

What I’d prefer, to save confusion & so nothing is lost, is to combine both accounts to my one “iCloud” account. However, when I try adding the iCloud email it always tells me the address is already in use (which it is, as it’s my second account).

Is there any way combining the two accounts can be done?

Thanks

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