I found this support forum post but the solution provided doesn’t work.
Edit (thanks to @moreeni@lemm.ee for the Stack Exchange link):
Solution - Go to Settings -> Home -> Enable Shortcuts -> Go to a new tab -> Google will be pinned by default, hover over the Google icon -> Click on the 3 dots menu -> Unpin
Yes, my default search engine is Ecosia.
I haven’t changed it manually though, I installed their extension and it changed the default; if this matters in any way.
You can add ecosia without the extension, just open the website, click the url bar and it’ll be among the search engines with a plus on top. Clicking it adds it
Thanks. Because of this post I was able to figure out how to change the search engine on my phone
Go into Settings. Under Search, remove all search engines except the one you want to use. They can always be restored later.