Credit Union Won't Give Me Access To My Deceased Husband's Part Of Our Joint Account

I didn't know how to put enough information in the title. This is in Colorado, US. My husband and I had a joint account with our local credit union for about 20 years. I think it was his account first and he added me, but still joint in both our names.

A year ago he died unexpectedly. I provided the death certificate and will to show that I was the only heir.

They claim that they cannot give me access to some things he set up in the account, specifically:

1. Any scheduled bill payments he set up - so the bills are getting paid at least, but I can't update those scheduled payments or see the history. I see the payments when they come out of the checking account. It's all the major monthly bills; mortgage, internet, etc.

2. An energy loan that was in his name only for our solar panels. I see payments go out but can't be sure they will stop when the loan is paid.

3. They claim they cannot transfer the bill pay schedule to me but offered to cancel them all so I could set them up again. I need to update a couple and do not want to stop my regular bill payments and have to set them up again. My mortgage payment increased and their suggestion is to set up a second bill pay schedule for the difference. I do not want to muddy the waters with the mortgage company.

I am the only heir, so it should be simple - as I inherited any debts, didn't I inherit all aspects of this joint account? I don't know why this restriction would be the institution's policy. I want to know if there's anything I can do legally. I suspect they just don't know how to change the status of the account. Why are they doing this?

This is more than annoying because of the situation. It's infuriating and demoralizing. Every issue like this related to my husband's absence is emotionally draining.

I did have a lawyer who drew up our wills, but when I asked him about this issue he basically shrugged. I know this is not where I get official legal advice, but if you could point me to somewhere I can research any laws related to this it would help.