Repair the credenza

I don’t know how the drawer guides on two of the drawers on the credenza in our dining room managed to get mangled and torn off. Yesterday I was looking for a new book of checks in the drawer where I keep the old check registers and books of checks and deposit slips, and the drawer came crashing down onto the floor. I was lucky it didn’t hit my foot! I found the mangled drawer guide inside the drawer. I don’t know who put it there, or when it was put there, but I was quite annoyed that nobody told me that it was broken so I could arrange to repair it! I hate when things like that happen!