Go back and read ALL of Reply#13.
It says very clearly that the A4988 will NOT work with NOTHING connected to the ENABLE pin. Your drawing AND your wiring photo were done from the diagram which ASSUMES that you know this. If you do NOT connect the ENABLE pin to GND. Nothing is going to happen , because TTL (do you know what that is ?) inputs FLOAT HIGH. Leaving unconnected , means it will be HIGH and ENABLE is an ACTIVE LOW input.
Every else you have said is irrelevant at this point with the ENABLE line floating.
Do you know how to read ?
Read the labels on all the driver pins and tell me what's wrong .
Hint: Turn your photo UPSIDE DOWN and compare it to the schematic.
SEE A4988 DATASHEET (PAGE 10)
Enable Input (E¯¯N¯¯A¯¯B¯¯L¯¯E¯ ). This input turns on or off all of the
FET outputs. When set to a logic high, the outputs are disabled.
When set to a logic low, the internal control enables the outputs
as required. The translator inputs STEP, DIR, and MSx, as well as
the internal sequencing logic, all remain active, independent of the E¯ ¯N¯ ¯A¯ ¯B¯ ¯L¯ ¯E¯ input state.
Do you , or do you not know that floating TTL LOGIC inputs FLOAT HIGH ?
What does that tell you about what you need to do ?
See the schematic on page 1 of the datasheet ? Do you see nothing connected to the ENABLE pin ?
(like your circuit photo)