On the CI Form/Record(Irrespective of class type), all the rest of the form loads as expected except for the CI relationship formatter and after a few seconds, we may end up seeing the below error (please refer to the screenshot), irrespective of the relationships being displayed.

All versions.

This issue happens because of 2 potential reasons-

1. OOTB, the number of relationships that can be shown on the CI relationship formatter is limited to 1000 and if the CI is expected to pull more than 1000 relations to be displayed, the formatter may fetch till 1000 and the error message 'Maximum relationship limit has been reached and not relations are shown on the formatter' appears on the formatter window.
2. In conjunction with the above point, a user has the ability to control the levels of CIs to be displayed in relation to the CI that's being referred. OOTB, the highest level is limited to 5. So, there can be all chances that from the relationship formatter properties, a user might have selected 5 levels of relationships to be shown and then that goes beyond the OOTB system limit of 1000 relationships. 

This can be controlled and fixed by 2 properties-

1. 'glide.ui.max_relations' - Specifies the maximum number of related CIs to display. As specified, the default value is 1000. This property can be added and the limit can be toggled to see if all the relationships can be displayed
   
   2. 'glide.ui.max_relation_levels' - Specifies the maximum level for displaying CIs in flat view before reaching the maximum relations limit. The default value is 5. This depth can be toggled as per the requirement to control what levels gets displayed on the relationship formatter.