After applying the 7.10.1 update, clients may experience a message when following a direct domain renewal link:

You do not currently have any domains that are eligible for renewal

An additional variable is required to determine the number of available domains on this particular domain renewal workflow.

Please apply the 7.10.2 Maintenance Release via the Utilities > Update WHMCS page.

A hotfix has been created for 7.10.1 only which adds the required vairable:

https://whmcs.community/files/file/132-core-14484-correct-single-domain-direct-renewal-link/