What are these small bumps on my arm?

I’ve had tiny bumps on my upper arm near my shoulder, I’ve had them for about 5 years, and nobody can explain to me what they are. I have tried to figure out what they are and these are my results: The’re not “Goosebumps”, the’re not present anywhere except from my elbow up, The’re not ingrown hairs, the’re not blemishes, and the’re not going away! please help me figure out what they are.