So from what I can make out of this Spreadsheet  you need to downgrade a level 6 HQ while your HQ is at level 6 before you can take it to level 7? And no requirements to downgrade a HQ at a given level before going to level 8 from level 7? 

This morning the plaroium server crashed (as usual) and when I arrived again I set out to raise the headquarters to level 20 but despite having met all the requirements the system did not update the headquarters, the problem is that plarium NEVER It gives answers to players who do not use a credit card since we are not a lucrative benefit for them but we are useless so that they spend time on us, here I leave the proof that we did everything correctly. 

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