My Fomo app balance dropped to zero and I need to know whether my other wallet is at risk

I bought roughly $100 of a memecoin through the Fomo app and briefly showed an unrealised gain of about 18%. When I checked again, the app displayed a zero-dollar balance even though it still showed me as a holder and the token itself had not collapsed.

Support told me that I had been hacked and asked whether I had clicked any suspicious links. I do not believe I had clicked a link that led to this. The incident made me worry because I use the same email address for another crypto account.

I have used Fomo for memecoin trades before without this problem, so the sudden zero balance was especially confusing. I am looking for practical guidance on what could have happened and what steps I should take to protect the rest of my crypto accounts.