When you migrate OBIEE from 10g or 18.104.22.168 or 22.214.171.124 to a newer version it is important to know the supported upgrade paths.
If your objective is version 126.96.36.199.x (for example the latest 188.8.131.52.10) then first you has to go to 184.108.40.206.0. Afterward you can patch the version with opatch to 220.127.116.11.x. This way is described here by Oracle. Bear in mind that all patches are cumulative so you only has to take the latest one.
If your objective is version 18.104.22.168.x then you can directly go to this version. There is no need to take a stopover. This way is described here by Oracle.