I have an indexer with an Enterprise License and I also have a search head. I know that there is no license for the SH, but there is a message on SH "your license will soon expire".
Could you please tell me how to fix that?
Generally you want to keep License Master role away from indexers and if the SH is the only other server, then License Master should be SH and Indexer should be License Slave. See below link for more information on how to configure License Slave.
is there a reason for having your license on the indexer and not in the SH ?
I suggest to put it on the SH and remove it from the Indexer.