Problem with promotional price for a selected group

[CosMarketing]

Describe the bug

We have the following problem with the plugin - after setting a promotional price for a selected role group on the product page, the promotion disappears by itself after some time. This does not apply to all products, but to most.

Please let us know what we can do to fix the error.

To Reproduce
Steps to reproduce the behavior:

1. Go to '...'
2. Click on '....'
3. Scroll down to '....'
4. See error

Expected behavior
I expect the set promotional prices for the group to remain until it is manually deleted.

Screenshots

Yesterday I set a promotional price for the "Hurtownia" group, and today the promotional price is not visible.

Software Versions

1. WordPress : 5.8.10
2. WooCommerce : 5.3.1
3. Role Based Price For WooCommerce : 3.3.7

Additional context