Here is how I would word it:
I always try to help my coworkers, as I am always eager to help others with anything. There were many times at my previous job when I helped somebody else.
Sometimes, new workers didn’t know how to do a particular task, and I was always eager to help them out. It was difficult at the beginning of the job to know everything about the system. The new workers had a lot of problems and questions, and they asked senior workers for help.
There were many times they asked for help, but now it is hard for me to remember all that. There were lots of such situations, and I can bring up one – somebody asked me to help them restore a customer's password.
Sometimes customers forgot their passwords and they wanted consultants to restore it. The procedure was quite difficult and the new workers didn’t know how to do this task. I was always eager to help. When I was a new worker, I also had some problems with the system. I could then count on my co-workers and get the help from senior workers.
In was natural for me to help. I have never refused to assist someone, but sometimes I was busy with a customer and I could not stop my conversation on the telephone, but if I had the time and opportunity, I showed them how to complete the task at hand. It was natural for senior workers to help the new ones with anything, such as a system, or tasks they didn’t know how to do.