Semi OT, but it’s Sunday Funday!
To improve working memory try dual-n-back app on app store. I got to n=7, if you can beat that you will have my respect! Bonus point, improving WM through DNB is one of the few exercises that will increase your IQ or at least it will help you keep a more complex line of reasoning or story in your WM will someone explains something to you... Only problem is that the training is brutal, you will find every excuse there is to quit training, it’s like legday for your brain...
To improve long term memory, fix sleep, if old consider boosting NAD+(NMN for example) and do some practice with mnemonic major system:
Mnemonic major system - Wikipedia
Get a book or watch some video about it. If you can memorize your passport numbers that’s a good start!