There is no problem is what you presented to us.

Do you perhaps change package at some point? 

package One;
...
use MyModule;
...
package Two;
...
functionOne()
...

[download]

&One::functionOne exists, but &Two::functionOne doesn't.

In reply to Re: Using a module twice giving a problem by ikegami
in thread Using a module twice giving a problem by Anonymous Monk

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