Compatibility setting in standby after changes in primary

Hi all,

Good day

We have two node rac on RHEL 7.6. Recently upgraded to 19c from 12.1 .  WE have standby database .

After upgrading to 19c it was initially with 12.1 compatibility  on both primary and standby . The log shippment was ok . Today I changed the compatibility to 19.0.0 on the primary

and didn't make the changes on the standby . I see error like the below in the alert log . 

Question

Should I be making changes in the standby too , as it has to update the spfile  like the below.Please advise

ALTER SYSTEM SET COMPATIBLE = '19.0.0' SCOPE=SPFILE sid='standby1';

ALTER SYSTEM SET COMPATIBLE = '19.0.0' SCOPE=SPFILE sid='standby2';