Texture Pack is not active on Realm

I wanted to activate the texture pack "conquest" on my realm (10 persons) and it all worked like intended. I did this with my mobile phone. Yesterday (around 4 days after creating the realm) i downloaded minecraft for windows 10 on my PC for the first time, logged onto the realm and the texture pack was still active. After playing a bit we went offline, and as soon we went back the texture pack couldnt be activated. I already tried all these tips REALMS-1347 but none of it worked. When  i am in the menu for the realm world settings, i also cant activate the button that make other players accept your texture pack. At least it dorsnt stays ticked. If you need any more Informationen i would be happy to provide it! Thanks in advance