If you are still in uptime and there is productive operation going on then you may go ahead ignoring the error
In general this is the rule of thumb :
Make sure that you have cleaned up all outstanding updates and for
4.x and higher, all outbound queue RFC calls by the JOB_RSVBCHCK_R or
JOB_RSVBCHCK_D phase (during downtime) at the latest.
Please see 689574 -> Section: Phase JOB_RSVBCHCK2
Section: Phase JOB_RSVBCHCK2
The text should say:
"If errors occur in this phase and you are still in production
operation you can skip these errors with ignore without entering a
password.