Physical Items Stuck at Customs

Hello everyone,

I have bought supporter packs that included some physical items recently.
And those items have arrived but are stuck at customs.
I would like to know what steps I can take to get those items.

The customs are asking me to provide documents proving the price of the items, the shipping cost and that I have paid for them. But also customs have received some kind of information on the value of these items since they specify that the hoodie costs 35$ and the t-shirt costs 15$.

Are we not suppose to provide such documents to the customs? Since we did pay the VAT for the pack the tax should already be included and my customs office should've received the IOSS number of the purchase?

I have made a couple of mistakes trying to retrieve the items (but hopefully not irreversible):
I have specified that those items are a gift, which did not work since GGG is a legal entity not a person.
I have sent an email to the GGG support on the 17 of February and for the Street Address that they have asked in the automated reply have provided the street number (thinking that it was necessary) I hope this wont mess things up.
After the first email I have received the response about 12 hours later.
I have also sent additional 2 emails to the GGG support (only today I read that this should not be done since it causes more delays) on the 19th and with a new topic on the 20 of February. Have not heard anything from them since.

The time for the package to be sent back has arrived today so I contacted the post office and they have extended the deadline by 10 more days.

Should I just wait for now and try to delay the sending of the package back by as much as possible?
Do I need to contact the GGG support again or that would cause even more delays for me?

Thanks in advance.