cannot mount old LaCie 1 TB external drive on new MacBook

My old LaCie external drives (1 TB) lack USB-C connectors. I am using old USB-A cable and adaptor. The drive shows up on the desktop for about 15 seconds and then it disappears/disconnects before I can do anything. I would like to reformat the external drive but it won't stay mounted. After 2 - 3 attempts, now it won't mount at all.

What is going on? The LaCies have my TimeMachine backups from my old (now dead) MacBook.

Now running OS 15.0.1 on MacBook Pro 14-inch Nov 2023.