Thank you for your question on the sewing Machine.
I am sorry that you cannot find the model number anywhere on the machine.
If it is an older flat bed machine it will usually be under the feed drop lever under the bed on the right side and it will have a model number starting with 148.or 158.XXXXXX. Some of the newer models start with 385.XXXXXX.
Some of the other models will have it on the back below the motor if the motor is exposed.
Otherwise it may be on the back side of the machine below the spool pins, but I think you would of seen it if it was at that location.
Could it be possible that it was removed for some reason?
Would it be possible to send me a close up picture the face of the machine and maybe I can figure it out.
I am sorry but I cannot picture the attached arm onto the presser foot screw that would restrict putting on a different foot. Unless it is a snap on foot and you have feet that need to attach directly to the presser foot bar.
Please let me know what you have found, and we can continue our troubleshooting based on that information.
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