There are currently two solutions for idle trademarks:

Authorize others to use it. In this case, the trademark rights are still yours.

Transferring a trademark, as the name suggests, means selling it to someone else. In this case, the trademark will no longer belong to you.

It depends on how you want to deal with it. If the trademark is not applicable for three consecutive years, others can apply to the Trademark Office for cancellation.

Hope it helps you~