Bedrock Realm Incompatibility - Boat Warning and Block Mismatch on Mobile

I would like to report a synchronization issue between the Bedrock Edition Realm and mobile clients.

Issue Summary:
After uploading a custom world with add-ons (mods) to my Realm, the following issue occurs:

• On PC (Windows 10, v1.21.120) → The world runs perfectly fine.

• On Mobile (Android, v1.21.120) → The game shows a “Boat” warning with the message:

  “Client and server disagree on blocks”
  Error Details:
  Transport: NetherNet:859
NetworkType: 4
Messaging: 14087652098291004206

Details:

• Both devices are on v1.21.120.

• All add-ons and resource packs are exactly the same.

• The same world runs correctly offline on both devices.

• When the same add-ons are used in another world, it can be uploaded to Realm and played normally.

• The issue started suddenly yesterday, without any change to the add-ons or world files.

• Removing all add-ons resolves the issue (so it is likely Realm-side synchronization or caching problem).

Steps to Reproduce:

1. Prepare a Bedrock world with custom add-ons.

2. Upload it to a Realm.

3. Try joining from both PC and mobile (same version).

4. Mobile device shows Boat warning and disconnects.

Expected Result:
Both PC and mobile clients should join the Realm normally if they are using the same version and add-ons.

Actual Result:
Only the PC client can join. Mobile clients show the Boat error message.

Possible Cause:
Realm may be caching an older version of the add-ons or world data for mobile synchronization.

Please investigate this issue, as it prevents cross-platform access to Realms with add-ons.

Thank you for your attention and support.