The # character is a terminating character by default. If the # character is entered while the router is waiting for additional digits, the # character is treated as a terminator and is not treated as part of the dial string or sent across the network.
If the # character is entered before the router begins waiting for additional digits then the # character is treated as a dialed digit.
To verify whether this happening, you can change the termination character by using the dial-peer terminator command in global config, try changing it to * and then change your destination pattern to begin with #.
Regards
Allan.
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