Lost my Safari tabs while merging Safari windows

I was trying to merge 498 tabs with a 1 tab that was accidentally opened in a new window, I foolishly tried to add the 498 tabs with the 1 tab window and the app crashed. Afterwards, the 498 tabs were lost and could not be found under 'merged windows' and the 1 tab became the default new window and became the only one left. Where are my other tabs and how can I get them back? These are ones that I have been keeping for years and I am very irate at its loss as I was about to stash them all away. I am using the latest iPadOS version.