2 Sites Pixel problem

We are planning to extend our business to other countries, so we decided to have separated sites for every country.

We duplicated site vizzor.si to domain vizzor.sk (for Slovakia market). All connections to previour domain were deleted. New site is hosted by the same hosting as first site.

Explanations of some terms for future understanding:
– site1 = vizzor.si site – main site
– site2 = vizzor.sk site – duplicated site
– pixel1 = pixel, connected to site1
– pixel2 = new pixel for site2

1. Site1 is connected by pixel1.
2. We connect pixel2 to site2
3. About 2-24h later, connection on site1 is changed to pixel2 automatically (site1 and site2 have the same pixel connected)
4. We reconnect site1 with pixel1.
5. About 2-24h later, connection on site2 is changed to pixel1 automatically (like on step 3)

We cannot connect different pixel for different page, because it is changed automatically so all sites has the same pixel connection.

All connection betweeen sites were deleted in php.
We also have another page (which was not duplicated) on different hosting and pixel there work normally (the same business account and everything, just different pixel).

Does anyone has any solution or any clue what could be wrong here?

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