Plot hole: Mando's ship was completely wrecked, but two mechanics fixed it to top performance level and aesthetic pleasantness in a time shorter than it took for the Child to eat a small packet of macaroons.
Suggested correction: His ship was badly damaged, but mostly repaired by the Mon Calamari. The remaining repair work was less complex, but still took place over the course of several days. A space-faring civilisation being able to repair a damaged ship is not a plot hole.
His ship is literally falling apart (we see pieces falling off as it moves), the engines are barely functioning and looks like hell. It's not at all a mistake that a "space-faring civilization" is "able to repair a damaged ship", it is when the editing of an episode makes it look like two dudes fixed to pristine condition a wreckage in the same time it takes for a kid to munch his cookies.