microsoft double account

HI there!

Please I am desperate, I need help!

I got 360 in a new laptop one week ago. Everything was ok. My account in Microsoft was ok, all good. '

out of the blue today I got a windown poping out saying :

It seems you have two account in Microsofr with the  same email.  which one do you one ( profesional or personal): 

I choose profesional

I choose wrong

Now in the history the last file was one from 2015.

how can I change my accound back to the recent one??

please, any help is good help