@VAparici this happens frequently with dynamic blocks and is caused by anonymous block names. If you select a block and do the LIST command, you’ll see that some of them have an anonymous name:
When the dynamic properties of a dynamic block are manipulated, the changes are stored behind the scenes as anonymous blocks. An anonymous block is created for each different state of the dynamic block in the drawing. The anonymous naming allows the same block to be different by changing it’s name for every different occurrence.
This answer doesn’t seem to fully explain how some of your blocks became anonymous in the first place, because it doesn’t seem like aligning the block to an object using the grip will add the anonymous name - so that part is still a mystery. But this means that you should be able to select the blocks by name in Dynamo after using the RESETBLOCK command.
Or just select them by their layer, that’s another way to do it.