If a transaction has failed, please contact the game's support making sure to provide the following details:
Your wallet ID
If available, the transaction ID (TX ID) of the failed transaction.
The date/time (including your time zone), of the failed transaction.
What actions were involved with the transaction?
For example, if you were merging units, what units did you merge, and what should you have gained.
Any other information that you feel is relevant.
In these cases, the more information that you provide, the easier it is for us to help you in a timely manner.