DS is 17 and works in a shop. He has specific set hours/days that he has to work as part of his contract. He has also provided his managers with his availability over and above the contracted hours he always works. This is provided on the shop's online staff portal.
DS was allocated a shift that fell on a non-contracted day and which fell outside of his availability. He messaged the manager who organises the rotas to tell them he would not be able to work the shift he had been given the following week as it was not on one of his contracted days and he had told them he was unavailable at the time of the shift.
The manager did not respond to his message, but DS decided that as he had now told them twice (by first providing his availability on the portal, and then in the message directly to the manager) that he would not be able to do the shift, he was within his rights not to go in for the shift. He is now worried he will be in trouble next time he is in work. AIBU that he hasn't done anything wrong? He has communicated his boundaries clearly and let them know he would not be able to do the shift with reasonable advance notice.